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THE
JOURNAL
THE LINNEAN SOCIETY.
ZOOLOGY.
VOL. XV.
LONDON: SOLD AT THE SOCIETY’S APARTMENTS, BURLINGTON HOUSE, AND BY LONGMANS, GREEN, READER, AND DYER, AND WILLIAMS AND NORGATE. 1881.
Dates of Publication of the several Numbers included in this Volume.
No. 81, pp. 1- 78, published March 30, 1880. 82, ,, 73-137, 5 July 31, 1880. 83, ,, L3d7—187, = September 3, 1880. 84, ,, 187-241, i November 20, 1880. 85, ,, 241-290, a3 March 25, 1881. 86, ,, 291-332, A September 29, 1881. 87, ,, 333-412, 3% October 4, 1881. 88, ,, 413-509, ss November 3, 1881.
PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET,
Bv6 AW
LIST OF PAPERS.
Page AuimaN, Professor G. J., M.D., LL.D., F.R.S., &.
The Anniversary Address of the President for 1879.—Some Re- cent Additions to our Knowledge of the Structure of the Wife OMI OVA Gy fetes eles csvset sheen atom Mceyoeaneie: evap atc te cape 1
On Limnocodium victoria, a new Hydroid Medusa of Fresh Water. (With 3 woodcuts.) ...... GO UIOO | GU OE Oe o ONC O 131
BELL, F. Jerrrey, Professor of Zoology, King’s College, London.
Note on an Abnormal (Quadriradiate) Specimen of Ambly- pneustes formosus. (Plate V. in part.) (Communicated by Dr. Pa OH Le Se) a verve mretele ayes avers Strate Cates aie lai ereraies ecole 126
On the Apparent Retention of a Sur-anal Plate by a Young Echinometra. (Communicated by Dr. J. Muniz, F.L.S.) (VAivabwiOOdeUt.)) ciaclaetsc spate eleleleyo a= Meme Ton BU COOOL CIS 318
Busx, Grores, F.R.S., Vice-President Linn. Soe. List of Potyzoa collected by Capt. H. W. Feilden in the North- Polar Expedition, with Descriptions of New Species. (Plate
oO) 5 bid mb lgin bles disc Arwen Rea SMES IAL Pherae Satta eda cs 231 Descriptive Catalogue of the Species of Cellepora collected on the ‘ Challenger’ Expedition. (With 4 woodcuts.)........ 34]
Supplementary Note respecting the Use to be made of the Chi- tinous Organs in the Cheilostomata in the Diagnosis of
Species, and more particularly in the Genus Cellepora. (Plates EOL, OG OUI) 3c 06 ce einai bal o enon bic ceo eC OUD 357
Burier, ARTHUR G., F.L.S. &., Assistant Keeper in the Zoological Department of the British Museum. Description of a new Genus of Moth of the Family Liparide from Madagascar. (With a woodcut.) ...............055 84
CAMPBELL, F. Mavtez, F.L.S., F.Z.S., F.R.M.S. On supposed Stridulating-Organs of Steatoda guttata, Wider., and Linyphia tenebricola, Wider. (With 2 woodcuts)...... 152 O certain Glands in the Maxillee of Tegenaria domestica, Black- Waa (Withyo wOOdCUtS.)) oii 6. se wea eos miagee alain ». 165
iv Page Carpenter, P. Herpert, M.A., Assistant Master at Eton College. On the Genus Solanocrinus, Goldfuss, and its Relations to Recent Comatule. (Communicated by Dr. W. B. CARPENTER, lds diols) (abies IDG O.G sag adodnndcoodss 35256 187
CoxBBoxp, Dr. T. Spencer, F.R.S., F.L.S., Professor of Botany and Helminthology Roy. Vet. Coll. The Parasites of Hlephants. (Abstract.) ..........0+++++0 333
Day, Francis, F.LS. &c., Deputy Surg.-Gen. Madras Army (re- tired).
iistinetsyand timotionsan Wishher).. tien ree eee 31 On the EHebridal Arcentine.” (Plate IV.) Fa 2-. s.osm eae 78 On the Specific Identity of Scomber punctatus, Couch, with SascomberMornn-y a Oelate Wa) ive a. eiekley alerts eet 146 Observations on some British Fishes ................ 0000: 310
Dosson, GEorGE Epwarp, M.A., M.B., F.LS., &e. Notes on Aplysia dactylomela. (With 2 woodcuts).........- 159
Duncan, Prof. P. Martin, M.B. Lond., F.R.S., F.L.S., &. On a Synthetic Type of Ophiurid from the North Atlantic.
@Plate se) eae teen eee eee ee Se eagele oe Seance peeaees 73 On an unusual Form of the Genus Hemipholis, Agass. (Plate ATES) BRN Ces tous iy rt SEA rR RS RRC Ri B EN ASE IE G's > G5 138
On a Lithistid Sponge and on a Form of Aphrocallistes from the Deep Sea off the Coast of Spain. (Plates XXIV. & XXV.) 320
Duncay, Prof. P. Martin, M.B. Lond., F.R.S., F.L.8., and Stuart O. Riptery, M.A., F.L.S.
On the Genus Plocamia, Schmidt, and on some other Sponges of
the Order EcurnoneMATA; with Descriptions of two addi-
tional new Species of Dirrhopalum. (Plates XXVIII. &
DO AD. GN pia aA ahs Biber od alien anita hed eens, ete iis Comcinke bos 476 Epwarp, Tuomas, A.L.S., Curator, Museum, Banff. On the Occurrence of the Norwegian Argentina silus on the Shore of the Moray Hinth Banttshine yr cneteleeir bier eels ee 304
Ewart, Dr. J. C., Professor of Natural History, University of Aber- deen.
On the Nostrils of the Cormorant (Phalacrocorax carbo). (Com-
municated by G. J. Romanus, F.R.S., Sec. Linn. Soc.) .... 465
19)
i Page Gopwin-Avsten, Lieut.-Colonel H. H., F.R.S., F.L.S. On the Land-Molluscan Genus Durgella, W. T. Blanford ; with Notes on its Anatomy and Description of a new Species. GEMS UNO OOO Solar Ud dute a ai dasele! dele die ele 'e e's 291
Happon, AtFrep C., B.A., Scholar Christ’s Coll., and Curator Mus. Zool. and Comp. Anat., University of Cambridge. On the Extinct Land-Tortoises of Mauritius and Rodriguez. (Communicated by Prof. A. Newron, F.R.S.) (Abstract.) 58
Hammonp, Artuor, F.L.S. On the Thorax of the Blow-fly (Musca vomitoria). (Plates IL. & NUE merit cca et cal oa ay oetaoe: aun Syrrokay by Act ctalwichisdosteiedsodages ane, Ma epn 5x 9
Herpman, W. A., D.Sc., F.R.S. Edinb., F.L.S., Demonstrator of Zoology, University of Edinburgh. Notes on British Tunicata, with Descriptions of new Species. I. Ascidiide. (Plates XIV.—XIX. and 3 woodcuts.) ...... 274 On Individual Variation in the Branchial Sac of Simple Ascidians 329
Lanxester, E. Ray, M.A., F.R.S., F.L.S., Professor of Zoology and Comparative Anatomy in University College, London. On the Tusks of the Fossil Walrus found in the Red Crag of pSontho anda CNDStLACU |) hayeueysbaueds esl spslerlpele ejexeleo¥ 9 xfc'e oiebah all's uc) 144
Lussock, Sir Jonny, Bart., M.P., D.C.L., LL.D., F.BS., F.LS., Vice-Chancellor of the University of London. Observations on the Habits of Ants, Bees, and Wasps :— Part VII. Ants. (Plate VIII. and 5 woodcuts.) .......... 167 Panty, Oey Ants.) (CWabhy oi wood cuits.) isc. ces oe eis © 362
Macponatp, Dr. Joun Dennis, F.R.S., Inspector-General R.N. On the Natural Classification of Gasteropoda. Part I. (Com- minicated by DriGs HH. Dosson, RS.) 5 ween. 16] Part II. (Communicated by Dr. G. E. Dosson, F.L.S.) .... 241
MicHagri, ALBERT D., F.L.S., F.R.MS. Observations on the Life-histories of Gamasine, with a view to assist in more exact Classification. (Plates XXII. & PONG ireco a Mendis den easies chars ai RMR eT er Sel ig css och siaanc chances 297
Miers, Epwarp J., F.LS., F.Z.S., Assistant in the Zoological Department of the British Museum.
On a small Collection of Crustacea made by Edward Whymper, Hsq., chiefly in the N.Greenland Seas; with an Appendix on additional Species collected by the late British Arctic Expe-
SDE CHMME eae UP UPI SAUSIM Haa a a2 uate 6) aPalay wl ehol sella alee ara aie 59
Notice of Crustaceans collected by P. Geddes, Esq., at Vera Cruz 85
vi
Ripiey, Stuart O., F.L.S8., Assistant in the Zoological Department, British Museum.
On two Cases of Incorporation by Sponges of Spicules foreign to them
nyie| Lae lie) eile) |v \>l)s lia) o) = Jie) ele) 6] fol» eke elielelip\ nse yellelisl © lel (elles) (eMeltelis) |v isiivilsltsialtaitents
Roviey, Stuart O., M.A., F.L.S., and Prof. P, Martin Duncan, M.B. Lond., F.R.S., F.L.S.
On the Genus Plocamia, Schmidt, and on some other Sponges of the Order Hcuinonrmara ; with Descriptions of two additional new Species of Dirrhopalum. (Plates XXVIII. & XXIX.)
oe
Sorsy, Henry C., LL.D., F.B.S., F.L.S., Vice-Pres. Geol. Soe. On the Green Colour of the Hair of Sloths. (With a woodcut.)
STEWART, CHaRuzs, F.L.S., Lecturer on Comp. Anat., St. Thomas’s Hospital.
Note on an Abnormal Amblypneustes griseus. (Plate V. in part.)
Watson, Rev. Ropert Boog, B.A., F.R.S.E., F.L.S., F.G.S., &e. Mollusca of the ‘ Challenger’ Expedition :—
Part V. Families SonENoconcuia, Trocuipm, HETERO- PHROSYNID®, LITORINIDM, CERITHIIDA, and genera and
SUSes Oe (Cid B yOOCleM)o 56 uoanodbaacocanoccss
Part VI. TuRRITELLID#Z. (With a woodcut.)............
Part VII. Families PyramMIpELLIDm, Naticripm, CassrpEA, TRITONID&H, and genera and species of
Part VILL. PLEvRoToMIDz
eee ee ee ec he oe ew CC
Part IX. PLEUROTOMID# (continued)
ere ee ere oe se eo oe ow
Page
149
130
413
Part X. PLEUROTOMID# (continued). (With 2 woodcuts.). 457
Vil
EXPLANATION OF THE PLATES. PLATE
I. } DissEctTIons.—Thorax of Blow-fly and other Insects, illustrative It, of Mr. A. Hammond’s researches.
III. Entarcep Views and Drtaits of Polypholis echinata, as de- seribed by Prof, Duncan.
IV. ARGENTINA SPHYRHNA in side view, and stomach and cecal
appendages. V. Ampiypyevstes.—Abnormal specimens of, illustrating Prof. Bell’s and Mr. Stewart’s papers. VI. Hemipnoris Waxzicut, a form of Ophiuran described by Prof. Duncan. VII. Macxeren figured by Dr. Day, as combining the characters of Scomber punctatus, Couch, and S. scomber, Linn. VIII. Camponotus INFLATUS, a new species of Honey-Ant. Charac- teristic parts referred to by Sir J. Lubbock. i Sprcrmens of Solanocrinus, Antedon, Actinometra, Pentacrinus, XL and Promachocrinus, illustrating Mr. Carpenter’s paper on XIL their relations to recent Comatule.
XIII. Arctic Potyzoa, illustrating Mr. Busk’s account of specimens obtained in the North-Polar Expedition.
XIV. )
2 Ne Ascrp1ans, and Structural parts of same magnified, being figures ae | illustrative of Mr. Herdman’s researches on the British
Tunicata. XVIII. XCIXG)
2 EE a as of the genus described by Lieut.-Col. XXI. Godwin-Austen.
XXII | GAMASINH, as coming under the observations of Mr. A. D. XXIII. Michael. poet
Spicuta of Lithistid Sponge and of a species of Aphrocallistes XKXV.
| from the coast of Spain, described by Prof. Duncan. XXVI. \ Cuitinous APPENDAGES of species of Cellepora, illustrating Mr. XXVII. Busk’s views on their value as characters for classification. ag XXIX.
EcuINODICTYUM, new species of. STRUCTURAL DETAILS of species of Dirrhopalum.
The two plates illustrating Mr. Ridley and Prof. Duncan’s paper on Sponges=Schmidt’s genus Plocamia.
ERRATA.
In page 78, Prof. Duncan’s description of Plate III.: fig. 4 should read fig. 4, a, 6, ec; and fig. 5, a, 6, e, should read fig. 5.
In page 186, top line, for “incredible” read inevitable; and on line 15 from top, after “ Australiam” discard the note of interrogation.
THE JOURNAL
OF
THE LINNEAN SOCIETY.
ANNIVERSARY ADDRESS OF THE PRESIDENT, Professor Anuman, M.D., LL.D., F.RS.
Some Recent Additions to our Knowledge of the Structure of the Marine Polyzoa.
[Read May 24, 1879.]
In following the course which I have hitherto chosen of making the address given at our Anniversary Meeting an exponent of recent progress in certain departments of biological science, 1 propose in the present instance to call your attention to some additions to our knowledge of the marine Polyzoa. The short- ness of the time at my disposal compels me to omit all reference to the embryological researches of which these animals have of late years been the subject ; the facts which I am about to bring before you must therefore be confined to those of a purely struc- tural character.
I, Structure or tHe Enpoprocrat Ponyzoa.
Nitsche, several years ago, contributed some very important facts on the anatomy of Pedicellina and of LZoxosoma*. He
* Sitzungsberichte der Gessellsch. naturforsch, Freunde zu Berlin, 1869, and Zeitschr. f. wissensch. Zoolog. vol. xx. 1871. LINN. JOURN.—ZOOLOGY, VOL. XY. 1
2 PROF. ALLMAN ON THE
especially called attention to the relations of the intestine, which in these genera opens, like the mouth, within the tentacular crown. This character thus becomes the index of a very distinct type of structure, in accordance with which Nitsche divides the Polyzoa into two great sections :—the Expoprocta, in which, as in Pedi- cellina, the intestine opens within the tentacular crown ; and the Ectoproctra, in which, as in the great majority of the Polyzoa, it opens outside of the crown.
Besides the long-known Pedicellina and the more recently dis- covered Loxosoma of Keferstein and Ciaparéde, the group of the Endoprocta now embraces the beautiful freshwater genus URNa- TELLA, described by Leidy*; while to the same group must be referred the remarkable marine genus AscopopariA, Busk MS., determined and carefully investigated by Busk in specimens from the ‘ Challenger’ Expedition, but not yet made the subject of a published notice.
Loxosoma has recently been studied by Oscar Schmidt +, who believes that he finds evidence that the apparent buds in this genus are really eggs detached from the ovary and developed on the body of the parent—a view which cannot be reconciled with other observations, especially those of Nitsche and of Salensky, who found such buds borne by other buds, in which, in consequence of their immature state, no ova could have as yet existed.
Salensky{ has described two new species of Loxosoma, and has made some important observations regarding the structure of this genus. Like all the other endoproctal forms, Loxosoma consists of a cup-shaped body supported on a peduncle. The peduncle consists of a parenchyma and a muscular layer surrounded by a cellular layer (endocyst), which is overlain by a homogeneous membranous layer (ectocyst). Its form differs much in the two species described by him. In one (L. Tethye) the peduncle is provided with a terminal gland-like organ ; in the other (L. cras- sieauda) no such organ exists. JL. crassicauda, however, fixes itself by means of a hardened homogeneous secretion, probably produced while the animal is young, and before the disappearance of the peduncular gland. The fixation of the animal by means of such a secretion seems to be characteristic of the species ; for the
* “On Urnatella gracilis,’ in Proc. Acad. Se. Philad, vol. vii. p. 191 (1854).
+ Arch. f. mikr. Anat. Bd. xii. p: 1 (1875).
t Salensky, “Etudes sur les Bryozoaires Entoproctes,” Ann. Sc. Nat. 6™* sér. tome y. 1877.
STRUCTURE OF THE MARINE POLYZOA. 3
other Loxosomas, which in their adult state are destitute of the gland (ZL. singulare and L. Kefersteinii), form no such secretion, but fix themselves by means of a sucker which terminates the peduncle.
The peduncular gland of L. Tethye is imbedded in a three-lobed terminal enlargement of the peduncle, and is composed of five or six large pyriform cells, with large nucleus. ach of these cells is prolonged into a very fine canal that unites with its fellows into a common tube, which traverses the middle lobe of the pe- duncular enlargement, and here opens externally by a pore.
It is a remarkable fact that even the species of Lowxosoma which when adult do not possess the peduncular gland, have it when young. The observations of Nitsche have proved this for L. Kefersteinii; and Salensky has confirmed it in the case of L. crassicauda, and Vogt in that of L. phascolosomatum.
The cup-shaped body of Loxosoma has its margin directed ob- liquely to the vertical axis, thus differing from the condition of the same part in the other genera, where the margin of the cup is transverse to the axis. Its wall cousists, like that of the peduncle, of a layer of nucleated cells which forms the endocyst, overlain by a homogeneous membrane which corresponds to the ectocyst.
The body-cavity, as in all the Endoprocta, is filled with a con- tinuous parenchyma. This consists of cells apparently destitute of membrane and provided with processes, which, by their union with one another, form a network between the body-walls and the contained organs—a condition which would seem to be uni- versal among the Endoprocta, and which separates them by a well-marked character from the Ectoprocta.
The form of the tentacles is that of a prism whose inner or oral side is provided with a ciliated groove. The outer side is com- posed of a layer of flattened cells, quite similar to those forming the outer layer of the body-walls. The axis of the tentacle is occupied by a parenchymatous tissue like that which fills all the body of the animal.
Large unicellular glands are described by Salensky as dispersed in the body-wall of L. crassicauda and L. Tethye. They are easily detected, being of a blackish colour and in considerable number. They occur chiefly at the edge of the cup and base of the tentacles, and consist of pyriform cells having their narrow ends turned towards the free surface of the body. Lach cell is filled with a brownish finely granular matter enveloping a sphe- rical nucleus.
4, PROF. ALLMAN ON THE
The muscles are nearly confined to the peduncle. Only a few fibres are found under the integument in the body, into which they are continued from the well-developed muscles of the pe- duncle. As in all the Endoprocta, the muscles which in the Ketoprocta are engaged in the retraction of the polypide are en- tirely absent.
Kowalewsky believed that the digestive canal of L. neapolitanum had but a single orifice common to the functions of ingestion and egestion—an error which Salensky rectifies by pointing out the difficulty of observing the commencement of the cesophagus from the point of view in which this part had been sought for by Kowalewsky, namely from the ventral side of the body.
Salensky has drawn attention to a remarkable gland-like appa- ratus unnoticed by other observers. It has the form of two bunches of cells plunged in the parenchyma of the body, one on each side of the intestine. The cells in each bunch are eight in number, of an ovoid figure, and consist of a transparent proto- plasm apparently destitute of nucleus, and surrounded by a deli- catemembrane. Hach cell is carried on a tubular peduncle, which is a continuation of its membrane ; and all the peduncles of each bunch unite into a common canal, which opens on the side of the body by a very minute orifice. Salensky regards these giand-like organs as having an excretory function, probably renal ; and it is impossible not to see in them bodies of great morphological sig- nificance, which admit of a comparison with the segmental organs of worms, and have an important bearing on the vexed question of the Vermal relations of the Polyzoa.
Salensky has further succeeded in demonstrating in Loxosoma a central nervous system, in the form of a ganglion which is placed above the stomach, between the end of the cesophagus and the beginning of the intestine. It is of an oval shape, and gives off nerves in different directions. Most of these lose themselves in the parenchymatous tissue of the body. The largest direct themselves from the two sides of the ganglion to the dorsal part of the animal. Hach of these, besides giving off many lateral branches, presents in the middle of its course w small thickening composed exclusively of nerve-cells, and, on approaching the in- tegument, at first attenuates and then enlarges into a pyriform knot, which becomes enclosed in one of a number of tubercles which form elevations of the integument on the dorsal part of the body, on each side of the longitudinal axis. These are doubtless sense-
STRUCTURE OF TIE MARINE POLYZOA. 5
organs. ach carries ou its summit a bunch of immovable sete. The cavity of the tubercle is filled by the pyriform nerve-knot, which thus lies just under the surface of the integument, and 1s in contact with the bases of the sete. Salensky compares these organs with the setigerous calcar of the Rotifera, and points to a close correspondence of structure between the two.
Nearly simultaneously with Salensky, and quite independently, Vogt* describes another previously unnoticed species of Lowosoma. It occurs parasitically in small tufts on the caudal extremity of two species of Phascolosoma, a genus of worms, and is hence named by its discoverer Loxosoma phascolosomatum.
The oblique direction of the cup-like body by which all the species of Loxosoma are distinguished, has suggested to Vogt a comparison to the hood of a cloak tied in front by astring. The space within the hood he names the vestibule; it contains the mouth, anus, and place of exit of the generative organs.
The peduncular gland observed in certain other species of Loxo- soma is altogether absent in the adult state of L. phascolosomatum, though it exists in the larva. Vogt further describes setigerous papille which he regards as organs of sense. Unlike the similar organs described by Salensky, these are only two in number, one on each side of the body. Vogt, however, has failed in his attempts to find any trace of a central nervous system.
The mouth, which, in the form of a very wide funnel, opens into the vestibule at the base of the tentacular crown, is provided with two projecting lips, one a button-shaped prominence on the ven- tral side, the other, longer and hook-shaped, on the dorsal, where it projects into the vestibule.
Vogt has convinced himself that L. phascolosomatum is dicecious. He describes in the male a thick-walled sac, which lies in the mesial line over the stomach, and which becomes filled with sper- matozoa. This communicates, by two very short canals, with two gland-like organs, which are situated one on each side of the stomach, and which he regards as testes, in whose cells the sper- matozoa are generated before passing into the median seminal re- ceptacle. He has seen the spermatozoa expelled from this recep- tacle into the cavity of the vestibule, and has noticed them esca- ping thence into the surrounding water.
* Carl Vogt, “Sur le Loxosome des Phascolosomes,” Archives de Zoologie ex-
périmentale, 1877. See alsoa translation and condensation of that memoir by Hincks in Quart. Journ. Mier. Sc. vol. xvii. new series.
6 PROF. ALLMAN ON THE
The ovaries, according to Vogt, occupy in the female exactly the same position as the testes in the male. The ovaare expelled from them one after the other, and pass into the vestibule, which may become loaded with them. Here they run through certain early stages of development, and are ultimately expelled as ciliated larve.
One can scarcely overlook the close correspondence between the organs here described by Vogt as ovaries and testes and those which Salensky describes as a glandular apparatus with a probable excretory function.
Loxosoma is regarded by Vogt as an archetypal form, from which that of the ordinary Polyzoa has been derived by successive modi- fications.
Il. HypoPHORELLA EXPANSA.
We are indebted to Ehlers for a valuable memoir on a very remarkable burrowing polyzoon, to which he gives the name of Hypophorella expansa*.
He met with it on the coast of Spickeroog, where it occurred in burrows which it had formed in the thickness of the tube-wall of Terebella conchilega. The completely developed colony is com- posed of two kinds of dissimilar members or zooids. Of these the one set is destitute of intestinal canal, and is capable of only non- sexual reproduction, while the other hasa developed intestinal tract, as well as sexual organs which give rise to fertile eggs, non-sexual reproduction occurring here only exceptionally. The intestineless members have the shape of long thin threads; he designates them ‘as “Stengelthiere.”” The intestine-bearing members are urn- shaped, or flask-shaped, and are called by Ehlers “ Nihrthiere.”’
The filiform zooids, or “ Stengelglieder,’’ form stolons by which the colony extends itself, and on which the nutritive zooids or ‘“‘Nahrthiere”’ are borne. The starting-point of the entire colony is a thread-like Stengelglied, which is developed from the larva. From the distal or growing end of this are produced in linear order a succession of similar filiform zooids, which together form a progressive filament, which burrows between the layers of the Terebella-tube. The distal end of this filament thus represents the youngest, as yet undeveloped filiform zooid.
From the single members (Glieder) of this long filiform stolon
* HE. Ehlers, “Hypophorella expansa, ein Beitrag zur Kenntniss der minenden Polyzoa,” Abhandl, der konigl. Gesellsch. der Wissenschaften, 1876.
STRUCTURE OF THE MABINE POLYZOA. 7
(if we except the oldest or basal member and the youngest or ter- minal) there spring in regular order lateral shoots, by which the stolon sends out on one side a series of filiform zooids like those of which it is itself composed, and on the other the zooids which form the flask-shaped or nutritive members of the colony. Hach component member of the burrowing stolon may thus carry on its distal end two opposite zooids, one of which is a filiform zooid, the other a nutritive zooid.
The filiform zooids push themselves between the layers of the tube-wall of the Annelid ; the nutritive zooids, on the other hand, perforate the inner layer, forming a circular orifice through which the animal projects its crown of tentacles into the lumen of the tube.
The component members of the stolon are dilated at their distal ends (where they carry the two opposite zooids) into a kind of flattened capsule. In the rest of their extent they present, under a low magnifying power, an obscurely ringed appearance. Each forms a completely closed tube filled with a clear non-cor- pusculated liquid. The wall is composed of a laminated chitinous ectocyst lined by a soft endocyst*, in which granules and fusi- form nuclei lie embedded, but which shows no differentiation into distinct cells. In the capsule-like dilatations there occur peculiar structures in the form of glistening, thin, straight bands, which are stretched from one side of the capsule to the other, and at their points of attachment pass into the protoplasmic substance of the endocyst. Hach of these bands contains a very distinct nu- cleus, but shows no further differentiation. They closely resemble muscular fibres such as are developed in the nutritive zooids; but Ehlers could obtain no evidence of contraction.
Unlike the filiform zooids, the nutritive zooids possess in most respects the typical structure of a Gymnolematous polyzoon. A peculiarity by which they are characterized consists in the pre- sence of two hollow horn-lke processes, which arise, one on each side, a little behind the orifice of the zocectum. Nothing can be asserted as to the significance of these processes. Their cavity does not appear to communicate with that of the zocecium.
The body-wall of the nutritive zooids consists of the same layers as that of the filiform zooids; the endocyst, however, is seen to
* Ehlers, on grounds which cannot be regarded as sufficient, refuses to
employ the terms “ectocyst” and ‘“endocyst,’ as well as “polypide,” “zow- cium,” and others now generally accepted by writers on the Polyzoa.
8 PROF, ALLMAN ON THE MARINE POLYZOA.
be much more distinctly differentiated into cell-territories. Em- bedded in its substance are oval nuclei, each of which is surrounded by a small area of protoplasm, from which fine filiform off-runners pass out to unite with neighbouring ones. We thus obtain the appearance of a set of stellate cells united by their radiating ex- tensions, and believed by Ehlers to undergo slow changes of form. Ehlers believes these to be of the same nature as the stellate cells which Claparéde* has observed in the walls of the marine Polyzoa, and to which he has referred the canal-system noticed by Smittt+ in the body-wall of Membranpora pilosa. Similar cells have been described by Nitsche in the marine Polyzoa.
In the completely retracted state of the polypide the appear- ance of a radially striated circular disk, perforated in the centre, may be seen a little within the orifice of invagination stretching across the tentacular sheath in the manner of a diaphragm. In the exserted state of the polypide this appearance is seen to be due to folds in the wall of the tentacular sheath; and this part of the sheath will then be found to form a transparent, short, cylin- drical neck with longitudinal ridges.
Tt will thus be seen that the great interest of Ehlers’s memoir consists in its making known to us a type of Polyzoa in which there is expressed a strongly marked dimorphism of the zooids with distinct functions allocated to each of the two forms which thus make up the complete colony.
* Claparéde, “ Beitrage zur Anat. und Entwickel. der Seebryozoen,” Zeit. f.
wissens. Zool. 1871. t+ Smitt, “Om Hafs-Bryozoernas utveckling,” Gifversigt, 1865.
ON THE THORAX OF THE BLOW-FLY. 9
On the Thorax of the Blow-fly (Zusca vomitoria). By Arrnvur Hammonp, F.L.S.
[Read June 19, 1879.]
(Puarss I. & IT.)
General Remarks and Descriptive Anatomy.
Tur following observations on the structure of the thorax of the Blow-fly embody a portion of the results obtained from a series of investigations conducted by myself at different times within the last few years on the thoracic structure of insects generally, and are offered to the Society with some diffidence.
Some time ago, on attentively considering the phenomena of wing-development in that common pest of our cellars and kitchens, the Cockroach (Blatta orientalis), I was induced to form the opinion that there exists in the prothorax of this insect parts which, however disguised, are the true homologues of the wings on the succeeding segments. My present object, however, is to submit such evidence as appears to me to bear upon the problem of the limits of the several segments of the connate thorax of the Di- ptera as exemplified in the insect which gives the title to this paper. So far as I am aware, our knowledge upon this subject has been confined to the statement that, in common with the two other orders of the Lepidoptera and Hymenoptera, the thorax of the Diptera consists mainly of the central portion of the thoracic region greatly enlarged at the expense of the other two. No definite attempt though has been made to fix by any process of reasoning the boundary which separates one of these segments from the other. According to M. Audouin, referred to by Newport *, “The parts capable of demonstration in each segment are:—on the upper or dorsal surface, the prescutum, scutum, scutellum, and postscutellum; on the inferior or pectoral surface, a single piece, the sternum, and on the lateral, two pieces, the epi- sternum and epimeron, on each side ; in addition to which there are also two evanescent pieces, which are of considerable size in some species, but scarcely distinguishable in others. These are the paraptera, portions of the thorax not articulating with the
_ * Article “Insecta,” Cyclop. of Anat. & Physiol., p. 911, where Newport summarizes from M. Audouin, Ann. d. Sci. Nat. vol. i.
LINN. JOURN.— ZOOLOGY, VOL. XV. 2
10 MR. A, HAMMOND ON THE
sternum, but with the episternum anterior to each wing, and the trochantin, articulating with the epimeron and coxa of the leg —the paraptera of the prothorax being, according to Audouin, absent.”
These parts constitute the external casing of each thoracic segment exclusive of the appendages, viz. the wings and the legs, and of the internal process known as the entosternum. Of those on the dorsal surface the scutum is the most prominent piece, and to it, in the alary segments, the articulations of the wings are affixed. In front of it is the prescutum, forming the anterior boundary of the segment, and generally bent downwards to form the horny partitions between the segments known as the phragmata. Following the scutum is the scutellum, a prominent portion of the thoracic skeleton, to which also, in conjunction with the scutum, the membranous portions of the wings (the alulets of the Diptera and Dyticide) are attached. Lastly, we have the postscutellum, which, like the prescutum, is generally bent downwards to form the phragma. These four pieces were regarded by Audouin* as the dorsal portions of four subsegments or annuli, of which the pectoral portions are less easily demonstrable on account of their being frequently confluent and not nearly so greatly developed. The parts forming the pectoral surface have been already sufii- ciently alluded to for my present purpose in the quotation from Newport. Although I cannot indorse the whole series of rela- tions thus indicated by Audouin, and typically exemplified in the structure of the Dyticide, the general correctness of his views is evidenced to my mind by the fact that on those chief points which separated him from Macleay +, Burmeister {, Westwood §, and Newport ||, to which I shall again have occasion to refer, I find the interpretation which Audouin has put upon these questions the more consonant with my own.
Where the separation of the three thoracic segments is distinct, as, for instance, in the Coleoptera, the determination of the limits of each is a matter of little difficulty. Where, however, on the contrary, they are more or less connate, as in the Hymenoptera, and especially in the Diptera, the difficulty is proportionally increased. In the former case this is illustrated by the fact of the dispute which raged over the question as to whether the piece
* Ann. d. Sci. Nat. tom. i. p. 118 (1824.) t Zoological Journal, yol. y.
+ ‘Manual of Entomology,’ translated by W. HE. Shuckard., § Introduction, vol. ii. || Op. cit.
THORAX OF THE BLOW-FLY. 11
called by Kirby * the collar was a portion of the prothorax or of the mesothorax, a question which is, I believe, generally now regarded as settled in the former sense. The different plates of which the thorax is composed can be conveniently studied by viewing them in their different aspects as seen from a dorsal, ventral, or lateral, an anterior or a posterior point of view, as the case may be. Let us first look at the thorax from an anterior point of view, as seen on removal of the head. Surrounding the cephalothoraciec foramen on the dorsal surface is a slightly thickened margin, the tergum of the prothorax (Burmeister’s pronotum f). <A pair of rami project from it. On either side of this are two small plates, bounded inferiorly by the coxa and posteriorly by the anterior thoracic spiracle ; these are the lateral plates of the prothorax, Audouin’s episterna. The cephalothoracic foramen is bounded inferiorly by two plates, which Mr. Lownet has called condyles, regarding them as parts of the last sub- segment of the head. From this opinion, however, I must dissent, as I shall have occasion hereafter to show$. Between the con- dyles is a small plate forming a peculiar organ, which he has called the cephalo-sternum, also looked upon by him as parts of the last cephalic subsegment. All these parts are indicated in my figure 5, Pl. I. Let us now turn to the dorsal surface. Here we find at its anterior angles two prominent portions, which in many species are somewhat lighter in colour than the surround- ing integument ; they are not marked off by distinct sutures, but their extent is sufficiently indicated by their colour and their protuberance. Burmeister (op. cit.) gives them the name of humeri, and says they are the same as his pronotum||. Lowne apparently does not notice them, or regards them as part of the mesonotum ; for, speaking of the anterior spiracle, he says (J. c. p- 72), “The mesothoracic tergum reaches over its superior margin and joins the prothorax in front of the spiracle.”
It will be evident from a consideration of my figure 6, Pl. I,
* ‘Introd. to Entomology,’ vol. iii. p. 548.
+t Burmeister’s terms, pro-, meso-, and metanotum, as applied to the entire dorsal surface of the respective segments, appear to supply a defectin Audouin’s . nomenclature, and will be used in the course of this paper as occasion requires, as also their opposites, viz. pro-, meso-, and metasternum.
t B. T. Lowne, ‘The Anatomy of the Blow-fly’ (Lond, 1870).
§ Posted, p. 28.
|| Shuckard’s translation, p. 82,
Ox
12 MR. A. HAMMOND ON THE
that the part here referred to as overreaching the spiracle, and described as part of the mesothoracic tergum, is none other than Burmeister’s humerus. I shall give reasons for thinking that Burmeister’s view is the correct one*. The anterior portion of the dorsal surface is formed by a rectangular plate, the anterior angles of which are cut off by the humeri. In front it extends almost to the margin of the cephalothoracic foramen, its central portion being only separated therefrom by the narrow ring of the prothorax. Behind the humeri it extends the whole breadth of the dorsal surface, and is bounded behind by a straight transverse suture just in front of the articulation of the wings. From the circumstance that this piece is distinctly marked off from the fol- lowing portion by a very evident external furrow and internal ridge, and, moreover, from the fact that it lies wholly in front of the articulation of the wings, I believe that it is the homologue of that part which in the Coleoptera especially is seen to occupy a similar position, viz. the prescutum, though in this order, as illustrated chiefly in the metathorax, it is bent inward to form the mesophragma. Following the prescutum is the large dorsal plate, the scutum, to which, as in all other insects, the wings are attached ; and this is again followed by the prominent and subtriangular scu- tellum, to which belong the alulets. These parts are shown in my figure 1, Plate I.
We will now look at the thorax from a lateral point of view as illustrated in Plate I. fig. 6. We here notice first the parts already mentioned, and in addition the following, viz. first, the anterior spiracle immediately behind the humerus, which is fol- lowed by a large subquadrangular plate, bounded in front by the spiracle, above by the prescutum, beneath by the sternum, and behind by a smaller plate to be presently described. Mr. Lowne (i. c.) has called this piece the episternum ; but although its rela- tion to the sternum would seem to justify this appellation, there are yet circumstances which seem to me decidedly to remove it from the piece so designated by Audouin. It will be noticed that, hke the preescutum, it is wholly and entirely anterior to the wing-socket, the latter being situate behind its superior posterior angle ; andin this important respect it differs entirely fromthe piece which in all the Coleoptera I have been enabled to identify with | Audouin’s episternum. It appears to me probable that this plate is
* Posted, p. 22.
‘
THORAX OF THE BLOW-FLY. 13
M. Audouin’s parapteron rather than his episternum. A similar difficulty attends the identification of corresponding portions of the thoracic casing of the Lepidoptera and Hymenoptera, whose con- formation in many other respects runs somewhat parallel. Behind this comes a succession of two or three smaller pieces, extending beneath the wing, and perhaps doubtfully distinct from each other. The first of these only requires special notice, as it is this piece which I look upon as Audouin’s episternum. It will be seen that it, too, may justly dispute the title with the piece in front of it, while its situation under the wing brings it more into harmony with the piece described by Audouin under the same name, and by Chab- rier* under that of “ clavicule scutellaire’”’ in the mesothorax and “plaque fulcrale”’ in the metathorax respectively, the anterior superior angle running up ina point under the wing-socket, which I regard as Chabrier’s “appuis de Vaile.”’ The remaining pieces of the series extend between the alulet and the posterior spiracle. Their precise relations I can say little about, save that, in common with other parts forming the posterior surface of the thorax, I purpose to show that they belong to the meso- and not to the metathorax ; the last of them is Lowne’s lateral plate of the me- tathorax. There yet remain two pieces seen in profile, viz. the sterna of the meso- and metathoracic segments, as they are re- garded by Lowne. This designation is unquestionably correct as regards the first, which is a large rectangular plate forming the greater portion of the ventral surface, and marked by a groove in the mesial line ; but with respect to the second I shall give reasons for thinking that this also is mesothoracic and not metathoracict. tt will be observed here that it is bounded superiorly by the pos- terior spiracle, where it is broadest. Towards the mesial line it is much contracted, and passes between the intermediate and pos- terior cox; a portion of its anterior border also abuts upon the sternum and another upon the episternum. The parts visible on the ventral aspect have been already mostly described. In front_are seen the humeri, and between them the condyles of Lowne; then follow the anterior spiracles, the episterna of Lowne (query, Audouin’s paraptera ?) ; and between them the large ster- num of the mesothorax, followed by the acetabula and coxe of the intermediate and posterior legs; and on either side of these are
* See Chabrier, “Essai sur le Vol des Insectes,’ Mémoires du Muséum
d'Histoire Naturelle. t Posted, p. 27.
14, MR. A. HAMMOND ON THE
the posterior spiracles, the plates between them and the wings, and Lowne’s metathoracic sternum (?). One portion, however, has not yet engaged our attention, viz. the narrow plate between the acetabula of the anterior coxe. This is called by Mr. Lowne the prosternum. He says*:—‘ It consists of a central portion and two cornua. ‘The central portion is a long narrow plate widest anteriorly ; it is grooved along the mesial line externally, and presents a slight ridge internally; posteriorly it sends a narrow plate along the edge of the mesosternum and between it and the posterior edges of the coxe on either side. This plate becomes broader externally to the coxa, and extends along the outer edge of its articulation, reaching the lower anterior margin of the anterior spiracle, where it unites with the lateral plate of the prothorax, and terminates in a curved point in front of the articulation of the coxa near its outer anterior angle behind the condyle.”
The description appears mainly correct, though I shall have occasion to differ from it in two particulars—first, the dissociation of the condyles from the central carina between the coxa, owing to their allocation in the “ fifth or last cephalic segment’’+ ; and, secondly, the association therewith of the cornua, by which I un- derstand the narrow plate which, as stated, runs along the edge of the mesosternum, and which I believe to be Audouin’s epime- TOM ste
Lastly, we will lock at the thorax from behind, having first carefully removed the abdomen. Some of the parts already re- ferred to appear again. Above is seen the scutellum, on either side the posterior spiracles with the plates surrounding them, and beneath are the coxe. In addition to these we have the two capitate organs called halteres, which, as I shall show, take the place of the posterior wings and a large surface of integument lying between them, separated superiorly by a narrow membra- nous conjunctiva from the scutellum, and having an emarginate contour beneath to allow a passage to the viscera. A semilunar space intervenes between its inferior margin and the lateral plates forming Lowne’s metasternum, into which project two slender apodemes connected with the halteres. About the centre of its length runs the junction of the first abdominal seement with the thorax, which extends between the bases of the halteres and
* Anatomy of the Blow-fly, p. 63. t+ Posted, p. 28. { Postea,'p. 27 (footnote).
THORAX OF THE BLOW-FLY. 15
separates the superior or external portion from the inferior or internal.
The whole of this large surface forms Lowne’s metathoracic tergum*, so that, according to his view, we have the whole of the pieces surrounding the thoracic abdominal foramen metathoracic, viz. the metathoracic tergum and the lateral and sternal plates of the same segment. That the same opinion was held by Bur- meister appears from the fact that he recognizes the same plate between the coxe as the metasternum}; and his figures on pl. xiv. of the thorax of Zubanus bovinus and Myopa testacea afford similar evidence. In assigning these plates, therefore, to the mesothorax, I am conscious that I shall differ from a weight of authority. With respect to the posterior spiracles also, I must differ from Westwoodt in assigning them too to the mesothorax instead of to the metathorax, whilst agreeing with him in regard- ing the halteres as appendages of the latter segment, in opposition to Audouin and Latreille, who looked upon them as abdominal.
So much for the external integument of the thorax. We must now shortly notice the internal processes which form the ento- sterna of the several segments. In the first place, we find the pair which are found at the posterior extremity of the presternum and reach the lower margin of the anterior spiracles; they are re- ferred to by Lowne§, and form, I believe, the prothoracic ento- sternum||. Similar horny rami arise from the extremity of the sternum in many Coleoptera: for example, in the mesothorax of Geotrupes stercorarius, Dyticus marginalis, and Rhizotrogus sol- stitialis. The mesothoracic entosternum extends the whole length of the sternal piece as a thin triangular vertical plate, with a pair of lateral processes for the insertion of muscles. The entoster- num of the metathorax arises between the posterior coxe and is much narrower. A projecting point of integument between them represents the whole breadth of Lowne’s metasternum (my meso- thoracic epimeron) in the mesial line.
Now in deciding the question as to which segment any one of the parts here described belongs, we may be guided by three con- siderations :—
1st. The analogy presented by other insects ;
* Anatomy of the Blow-fly, p. 65. t Shuckard’s translation, p. 85. t Westwood’s Introduction, p. 500. § Op. cit. p. 63. || Posted,”p. 28.
16 MR. A. HAMMOND ON THE
2nd. The evidence derivable from developmental change ; 3rd. That obtainable from a consideration of the nervous and muscular systems.
Considerations of Analogies in divers Insects.—I may observe that the three orders of hexapod insects associated by Packard* under the name of Metabola, viz. the Lepidoptera, the Hymeno- ptera, and the Diptera, beside the point of resemblance pointed out by him, have this in common, viz. the excessive development of the mesothorax at the expense of the preceding and following segments. That thisis broadly the case is, I believe, an admitted fact irrespective of questions at present under discussion; and it will be worth our while to consider what relation this prepon- derance of the mesothoracic over at least the metathoracic region bears to the development of the wings and to their effectiveness as organs of flight. Of the three orders it may be said that the Lepidoptera is that in which the size and effectiveness of the pos- terior wings are most nearly approximated to that of the anterior f. The posterior wings of the Hymenoptera are decidedly inferior to the anterior in size ; and it may perhaps be presumed that their efficiency as organs of flight 1s subordinate to and dependent upon the former, whose movements they are evidently formed to follow. Lastly, in the Diptera, the posterior wings are only found under the guise of halteres, and for purposes of flight are entirely ob- solete.
Thus in these three orders we are brought, by a succession of stages, from a condition in which the size and effectiveness of the wings are somewhat equal, to one in which the posterior are atro- phied, and the power of flight is entirely concentrated in the me- sothorax. Let us see if we can trace a similar succession in the development of the segments themselves. If we can succeed in showing that the comparative development of the two alary seg- ments in the Lepidoptera and the Hymenoptera is in proportion to their wing-power, as I may term it, we shall then have an a priort ground for thinking that the comparative development of the segments of the Diptera follows the same rule; in fact, that the metathorax is almost as obsolete as the wings, and that nearly the whole of the thoracic region is mesothoracic.
* Guide to the Study of Insects, p. 104.
t From the absence of longitudinal dorsal muscles in the metathorax of the
Lepidoptera, I incline to the opinion that even in this order the posterior wings are subordinate to the anterior.
THORAX OF THE BLOW-FLY. 17
But in order to do this we must first decide any disputed ques- tions that may arise as to the limits of the thorax in these two orders. I believe that as regards the Lepidoptera there is no dispute as to the limits of the metathorax. In Liparis salicis (Pl. II. fig. 9), behind the lozenge-shaped scutellum of the meso- thorax, we find the metathoracic scutum visible as a triangular Space on each side, the mesothoracic. postscutellum and the metathoracic prescutum both being developed inwardly ; this is followed by a minute scutellum and postscutellum, the latter also developed inwardly. Thus it will be seen that though of considerably less extent than the preceding segment, the meta- thorax has still a very appreciable breadth to correspond with its wing-development. Turn we now to the Hymenoptera. Here we are at once met with an old and hotly-disputed controversy. Audouin* and Latreille* believed that the posterior portion of the thorax in this order is not strictly thoracic—that is, that a portion of the fifth segment of the body entered into its ccm- position; while Macleay} was of opinion that the said portion was the scutellum of the metathorax enormously enlarged; and Westwoodt seems also to have regarded it as thoracic§. Ido not know that this question is regarded as settled even now, although the view taken by Packard || is, so far as concerns the Hymenoptera, similar to Audouin’s and my own; and I think the balance of opinion inclines that way]. It will be evident, how- ever, on a little consideration that the decision of this question must largely affect the course of our reasoning, for if we adopt Macleay’s views we shall have in the Hymenoptera a metathoracic development out of proportion to that of the posterior wings. I will therefore advance a few arguments to show that in this matter Audouin and Latreille are right as opposed to Macleay ; and in the first place draw attention to the two figures illustra- ting different stages of the development of the pupa of the
* See Westwood’s ‘ Introduction,’ vol. ii. p. 75.
t Zoological Journal, vol. v. p. 172. : t Tom. cit.
§ Burmeister and Newport were also opposed to Audouin on this point. See Shuck. Transl. Burm. p. 235, and Newport’s “ Insecta,” Todd’s Cycl. Anat. and Physiol. p. 55.
|| Packard’s Guide to the Study of Insects, pp. 67 & 109.
{| Subsequent to the reading of this paper, I have noticed that Sir John Lub- bock and Dr. Ratzeburg take the same view. See abstract, ‘The Anatomy of Ants,” Journ. Linn. Soc., Zool. (No. 80), vol. xiv. p. 7388. I may also quote H. Reinhard as supporting a similar view, vide Berlin. entom. Zeitschr. 1865, p. 207.
18 MR. A. HAMMOND ON THE
Humble-Bee from Packard *. In the first of these the fifth seg- ment of the body, the thoracico-abdominal segment of Newport, is seen to follow the alary segments and to be very similar to the succeeding abdominal ones, differing only from them in the form of its oblong spiracle, by which, however, it is easily and certainly recognized in the succeeding stage, where it is seen that the tho- racic abdominal incisure has taken place behind it, including it with the thorax. Iffurther evidence be required, I would point out that the Hymenoptera are not so exceptional in this matter as may be thought, and that the Coleoptera, as a rule, if not also the Heteroptera, exhibit a similar structure. That the Coleo- ptera do so has long come under my notice ; and I believe Audouin pointed out the same thing. If we look at the dorsal surface of Rhizotrogus, Geotrupes, or Dyticus, we find in either case the dorsal plate of a segment whose ventral are has disappeared (the segment is ventrally atrophied). This dorsal plate is unmis- takably the first of the abdominal series, and furnished, like all _ the succeeding ones, with a pair of spiracles, differing from the others chiefly in being larger. It is quite distinct from the meta- thorax, following, as it does, the inwardly developed and obtusely triangular postscutellum (see Pl. IT. fig. 15, for postscutellum of Rhizotrogus). In default of its own ventral arc, however, it is thrown forward, as it were, upon the dorsal surface of the meta- thorax, or the ventral surface of that segment is produced under- neath it so as to supply the place of the lost ventral are. It is as if the great development of the ventral surface of the metathorax had absorbed that of the next segment. A like conformation, I believe, prevails in many Heteroptera. Newport +, I ought to add, has noticed a general atrophy of the fifth segment of the larva in insects, though he does not appear to have connected it with the ventral atrophy of that segment in the imago to which I have re-
* «On the Morphology of Insects,” Proc. Boston Soc. Nat. Hist., Feb. 1866, p- 282, and the figures on p. 294.
t+ I cannot quite understand how it is that Packard seems to have ignored this fact ; for, in the paper alluded to in the previous note, he says (p. 291), “The Hymenoptera differ from all other insects in having the basal ring of the abdomen thrown forward upon the thorax.” The phenomenon is, I admit, not so strikingly marked in the two other orders as in the Hymenoptera; still it is, I venture to think, very pronounced, as I have endeavoured to show. Amongst the Heteroptera I would adduce the case of Coreus marginatus as the result of my own observation.
{ Todd’s Cyclopedia of Anatomy, “ Insecta,” p. 28.
THORAX OF THE BLOW-FLY. 19
ferred. In general the dorsal plate of the atrophied segment is about equally united with the thorax and the abdomen; but instances occur in which it approximates more closely to the former ; and as this brings it nearer the structure of the Hymenoptera, I have illustrated it in the case of Goerius olens (Pl. II. fig. 18). It will be remarked that the metathoracic postscutellum, which is usually developed inwardly to form the metaphragma, is here raised to the surface, forming the triangular piece between the two halves of the dorsal plate of. the atrophied segment, which, as usual, is furnished with a pair of spiracles, and is separated by a broad membranous conjunctiva from the first of the true abdominal series, its lateral margins being conterminous with the epimera of the ventral surface of the metathorax. Precisely the same thing has happened in the Hymenoptera, both petiolated and non- petiolated, only that in the former the thoracico-abdominal incisure being so much deeper and taking effect more on the dorsal sur- face, the union of the dorsal plate of the atrophied segment with the thorax becomes more striking, and therefore seems to have attracted exclusive attention.
The phenomenon is well seen in the Humble-Bee, of which I have given a drawing (Pl. II. fig. 6), where it will be seen how large a portion of the posterior surface of the thorax is occupied by this plate, reducing the metathorax in the mesial line at least to a mere ridge between it and the scutellum of the mesothorax, with a small triangular expansion on either side, to which the bases of the posterior wings are affixed. The section of the me- tathorax in the mesial line is shown in fig. 5, and it will at once be seen that, viewed in this light, that segment is now reduced to something like conformity with the subordinate character of its alary appendages. It might be expected that these organs, which are (in virtue of the hooklets by which they are united with the anterior pair) evidently formed to follow the movements of the latter and depend on them for their motive power, would require little or no provision of muscular force for themselves ; and accordingly we find an almost atrophied metathorax and no muscles in it.
We now see therefore that in the two orders of the Lepi- doptera and Hymenoptera the development of the segment is proportioned to the development of the wings. Surely, therefore, there is good @ priori ground to expect that in the Diptera the same rule will hold independently of the reasons to be presently
20 MR. A. HAMMOND ON THE
adduced, and that we shall find the metathorax of this insect to be as obsolete as are the alary appendages it carries.
Let us see now how the view of the thoracic structure of the Hy- menoptera thus advocated bears upon the position of the spiracles. Does it introduce an element of harmony into the study of this order as compared with other insects, or one of additional per- plexity ? and, finally, what is its effect on the location we may give to these organs in the Diptera? I gather from a passage in Westwood* that Latreille has made the observation that the metathorax in insects is never provided with spiracles. The observation is a good one, though not free from error, I venture to think, in the induction he draws therefrom, that they (and the halteres in consequence) are abdominal appendages. Of course, on his view of the Hymenopterous structure, they are excluded from the metathorax of that order inasmuch as, in his opinion also (as I have just mentioned), they occur on that portion of the body which belongs to the fifth or atrophied segment; and so far as I am acquainted, with the exception of the Diptera, there is no other order of insects in which a metathoracic spiracle may even be thought to be observable in the zmago. By regarding, there- fore, the posterior spiracle of the Diptera as mesothoracic, we shall introduce this element of agreement into the structure of the class-—not indeed by thrusting it, as Latreille did, into the abdomen, that is, by removing it backward from the metathorax, but by the converse process of removing it forward to the meso- thorax. We shall then have the metathorax in every order of insects devoid of a spiracle. That the posterior spiracle should be mesothoracic is absolutely essential to my argument, since it is surrounded by plates which I propose to show also belong to that segment.
But again, so far as I am acquainted, in every case where the limits of the thoracic segments are not subject of discussion, the position of the thoracic spiracles is, roughly speaking, between the segments, one pair between the pro- and mesothorax, and another pair between the meso- and the metathorax, though in some orders the latter are suppressed. Both pairs occur, for example, in the Ccleoptera and Lepidoptera; one only in the Hymeno- ptera, viz. the anterior. I say roughly, because I think there is really no debatable ground between the segments, and that any
* Westwood’s ‘ Introduction,’ p. 500.
THORAX OF THE BLOW-FLY. 21
given portion of the tegumentary structures must belong to one or other of those between which it seems to occur; and it will, I think, be found that the spiracles are in every case more nearly approximated to the segment in front of them than to that behind. Indeed I have noticed that the largest tracheal branch of the spi- racle between the pro- and mesothorax of Acrida viridissima pro- ceeds immediately down the fore leg to that peculiar organ in the fore tibia which has been supposed to be connected with the sense of hearing.
From this and similar indications I think that the spiracle is always the property of the posterior surface of the segment in front of it. And this is an additional reason for thinking that the posterior spiracles of the Diptera are mesothoracic, viz. that they are thus made to occupy the posterior or postscutellar region of the segment to which they belong. That they should in the Blow-fly be surrounded by well-developed corneous plates instead of membranous integument, is only an indication of the general fact that the postscutellar region has participated fully as much as the other portions of the mesothorax in the exceptional development which the segment has received in this order.
Evidence fram Developmental Change.—In a paper read three years ago before the Quekett Microscopical Society, “On the Metamorphosis of the Crane-fly and of the Blow-fly,” I took occasion to notice the dorsal appendages on the thorax of the pupa of these insects. I believe that these processes, which are indicated in my figures (Pl. II. fig. 1 and Pl. I. fig. 18), are the proper dorsal appendages of the prothorax, corresponding on that segment to the wings on the following one. The purport of their being seems to terminate with the pupa state; and in the imago their development as appendages seems to be arrested. As I endeavoured to show on that occasion, the fact of their being the serial homologues of the wing is not only attested by their position, but by the manner of their development, arising, as they do in either case, from a special imaginal disk, which, in the Blow-fly at least, had hitherto escaped notice from its minuteness.
This disk is shown in the case of the Crane-fly (PI. II. fig. 12), where it will be seen to correspond exactly in position to those of the wings and halteres which follow it, viz. a little outside of, and posterior to, that of the corresponding leg. The corresponding disk of the Blow-fly is situated just behind the
22 MR. A, HAMMOND ON THE
anterior spiracle of the larva immediately under the integument, and partially surrounding the anterior termination of the main trachea. I think that in this case similarity of development is a strong argument in favour of similarity of homological relation- ship ; and again it may be asked, if they be not the homologues of the wings, how are we to regard them? To look upon them as abnormal productions would, I submit, be contrary to the whole spirit of philosophical inquiry ; and what other opinion we can form I know not. If, then, they be the proper dorsal appendages of the prothorax of the pupa, then the imaginal structures found immediately underneath them must in all probability correspond, and be prothoracic too. But these structures are the humeri to which I have had occasion to refer. Therefore, with Burmeister, I must look upon these parts as prothoracic*, and consider them as the homologues of the posterior angles of the collar of the Hy- menoptera, the homologous parts in both orders being followed immediately by the spiracle.
But it is not only in the prothorax that the observation of de- velopmental change will afford a clue to the division of the seg- ments. In the pupa of the Crane-fly the dorsal surfaces of the meso- and metathorax are sufficiently and distinctly marked, the former being as conspicuous for its extent as the latter for its contracted dimensions ; and, strange to say, their dorsal appen- dages are not yet recognizable as a pair of wings and a pair of halteres, but as two pairs of undoubted wing-cases similar to each other in every respect but that of size. It is only when we sepa- rate the latter pair and examine them carefully with a lens that we can persuade ourselves that the nascent organs within them are not really wings, but the familiar halteres (see Pl. II. figs.3 & 4). They are, so far as I judge, unquestionably modified and abortive posterior wings, appendages of a metathoracic segment, however, reduced, and by no means abdominal, as was supposed by Latreille.
Again, on carefully removing the integument from the dorsal surface of the Crane-fly pupa over the posterior portion of the mesothorax, in front of its junction with the metathorax I disclosed the plate marked ps in the drawing of the imago (Pl. II. fig. 2), which I must therefore regard as mesothoracic. This plate is nearly horizontal in the Crane-fly ; but a compa-
* Anted, p. 12,
. THORAX OF THE BLOW-FLY. 23
rison of the two insects convinced me that it corresponds with the upper or external portion of the vertical surface which Mr. Lowne (op. eit.) calls the metathoracic tergum. Tor this reason also, therefore, I must hold this to be a mistake, and that the external portion at least of the surface in question belongs to the meso- and not to the metathorax.
As to the Muscular and Nervous Parts—But fully as cogent as either of the foregoing considerations is the evidence to be derived from an examination of the muscular structure. The nervous system of insects presents, to some extent, the repetition of parts observable in the integument. ‘There is generally in the larva a pair of ganglia with corresponding nerves for each seg- ment. Owing, however, to the concentration of the neryous centres in the thorax of the imago (a concentration which, in the Diptera, is carried to an extreme point), and their consequent fusion into one large nervous mass, it is less adapted to the study of homological relations than the muscular structure. ‘The latter, however, appears to me so obvious and so comparatively easy a means of discrimination, that any diagnosis of external relations that does not take it somewhat into account must of necessity be pro tanto imperfect. The subcuticular muscles of larve present a very uniform repetition. Hach segment has its own set of mus- cles distinct from those preceding and following it. I will not say that such a thing never occurs as the existence of a muscle extending across two or more segments, for I know at least of one instance in which this certainly appears to be the case*; still, as arule, observable not less in the imago than in the larva, each segment is provided with its own muscles; and the connate condition or any approximation to it of two or more segments is not, so far as | know, accompanied by any fusion, either real or apparent, of their respective muscles.
To illustrate this, it will be necessary to mention that the tho- racic muscles of insects assume two different principal directions f, a longitudinal and a lateral or vertical one. The former occupy
* This occurs in the larva of the Crane-fly; and a similar instance is men- tioned in Sir John Lubbock’s paper “‘On the Muscles of the Larva of Pygera bucephala” (Trans. Linn. Soc. vol. xxii. p. 174), being that marked No. 2 in the first Plate attached thereto.
+ For a more complete account of the muscular structure of the thorax, sea “ Hssai sur le Vol des Insectes,” par J. Chabrier, in Mémoires du Muséum d’His- toire Naturelle, p. 410.
24 MR. A. HAMMOND ON THE
the central portion of the thoracic cavity towards the dorsum, and are chiefly conspicuousin the alary segments, and (with the exception of the Libellulide) more especially of such insects as are remarkable for their power of flight, in the production of which, as is shown by Chabrier, they are chiefly instrumental. They fallin two divisions, one on either side of the mesial line, as may be seen in Plate I. figs. 8,10, & 11, and in Plate II. figs. 5, 10, & 11. They extend from the prescutum to the post- scutellum of the segment to which they belong, in every insect with which I am acquainted, and are the “‘ muscles dorsaux au abaisseurs des ailes”’ of Chabrier, the recti dorsales of the larva.
In the Coleoptera, where the thoracic segments are unmistak- ably distinct and the phragmata well developed, their attachments are equally clear; here, however, they are chiefly confined to the metathorax, as the faculty of flight in those insects resides in that segment. In Acrida viridissima we have an example where that faculty is resident in both segments; and accordingly we find that the longitudinal muscles are present in both (see Pl. IT. fig. 11); and though the two alary segments are much more inti- mately united in this insect than they are in the Coleoptera, the . two sets of muscles are perfectly distinct, the length of each being coextensive with the limits of the segment to which it belongs.
In the Lepidoptera the same rule holds. The anterior wings of these insects would appear to be the chief agents of flight ; for we find the dorsal longitudinal muscles confined to the meso- thorax, the vertical ones only being found in the succeeding seg- ment. They extend from the prescutum to the postscutellum, from the pro- to the mesophragma, both of which partitions are well marked. See Pl. II. fig. 10, which represents a section of the thorax of Liparis salicis.
In the Hymenoptera a somewhat singular conformation exists, which was first, I believe, pointed out by Macleay. The meso- thoracic postscutellum is detached in the mesial line from the scutellum, and only remains attached by its lateral extremities, so that the narrow rim of the metathorax follows immediately upon the scutellum of the preceding segment. Nevertheless that the detached septum thus formed is the postscutellum of the mesothorax is evidenced, as Macleay says, by the fact that when
THORAX OF THE BLOW-FLY. 25
the meso- is separated from the metathorax, it always comes away with the former. In the mesial line it projects far backwards into the posterior portion of the thoracic cavity so as to leave but little space between it and the posterior wall, which, as I have said,is formed by the dorsal plate of the fifth segment. Thus the longitudinal muscles of the mesothorax, which are the only tho- racic longitudinal ones developed, pass from it to the prescutum, across the minute groove of the metathoracic tergum and the cavity of the mesothoracic scutellum, as may be seen in Plate IT. fig. 5, which represents a longitudinal section in the mesial line of the thorax of the Humble-Bee. ‘There is no fusion of the muscles of the two segments. The mass of muscles which nearly fills the united cavity of three segments belongs but to one of them, viz. the mesothorax ; the metathoracic muscles, both longi- tudinal and vertical, being no longer required, are altogether obsolete.
Now for the application, so far as the longitudinal muscles are concerned. Plate I. fig. 8 shows the longitudinal muscles of the Blow-fly. They are seen to extend from the mesothoracic pre- scutum in front to that vertical posterior surface which Bur- meister and Lowne regard as the metathoracic tergum, but which, I venture to submit, is again, as it has been shown to be in all previous cases, the mesothoracic postscutellum, the mesophragma, and not the metaphragma. If it be otherwise, we shall have what I can find no other instance of, viz. a commingling of the prin- cipal muscles of two segments into one homogeneous muscular mass.
Again, be it observed from Plate I. figs. 8 & 11, that although the longitudinal muscles extend in the mesial line almost to the verge of the cephalothoracic foramen, they have not suffi- cient breadth to reach the anterior angles where the humeri are situated. It will be obvious that if this were the case, I could no longer hold the humeri to be prothoracic; but as it is, the avoidance by the mesothoracic muscles of these portions of the integument is, 1 submit, significant of the correctness of my view.
Further, let us see what may be learnt from a study of the transverse or vertical muscles of the thorax, proceeding on the assumption, warranted by general observation, that none at least of the principal of these can have their origin in one segment and
LINN. JOURN.—ZOOLOGY, VOL. XY. 3
26 MR. A. HAMMOND ON THE
their insertion in another*, and that where two segments are concerned there is sure to be more or less repetition of the mus- cles presented to view.
Let us glance for one moment at the muscular structure of 4ishna grandis. This insect is remarkable for its power of flight, and yet, contrary to the general rule, the longitudinal muscles are almost obsolete, the deficiency being made up by the number and high organization of the vertical ones. The alary segments are not very clearly separated externally, but internally an inspection of these vertical muscles shows clearly that the united cavity they occupy is formed of two segments. After removing the two principal masses which towards the mesial line are attached to the bases of the wings, and which obstruct the view of those behind, we find a number of others which have their insertions formed in a peculiar and very beautiful manner by a round plate, or “cupule”’ as Chabrier calls it, to the concave surface of which the muscles are attached, while from the other proceeds a tendon to the point requiring motion. These muscles, with the excep- tion of the last, are repetitions in two sets, 1234,1234 (see Pl. II. fig. 14), showing the existence of two segments.
But there is no such repetition in the vertical muscles of the
* Tf there be any doubt felt as to the correctness of such an assumption, let us look a little further into the matter. Passing by my own observations on the point, though the statement is founded mainly upon them, I may refer to the figures of Lyonet, in his Anatomy of the Larva of Cossus ligniperda, and to Sir John Lubbock, “On the Larva of Pyg@era bucephaia,” Linn. Trans. vol. xxii. p- 173. Of the following corresponding lateral muscles in the two insects, viz.
a Lyonet = 37? and 38 Lubbock,
B ,, =49 and 50 3 yy ae ena 6 ” = 51 ” 2 4 sieenle 9, Op sSaiipemclats — 4, m ” = 40 ” n ” = 43 ”
only the four marked thus (?) appear to offer a shade of doubt in this respect ; and these cases are indeed, as I may say, doubtfulones. The question is not ex- actly whether they actually cross the border-line between the segments, but rather whether they are attached by one extremity thereto, and that, in the caseof 0 =35, only in a partial sense, the anterior fasciculi only being in question.
s
THORAX OF THE BLOW-FLY. QT
Fly, in which three principal masses are observable (Pl. I. figs. 9, 10, & 11), the anterior being the “ sternali dorsaux ’’ of Chabrier, and the posterior his “ costali dorsaux”’; the intermediate one I am uncertain about.
Inasmuch, therefore, as there is no repetition, the muscles, I submit, are those of one segment. Again, the central mass of vertical muscles connects the anterior portion of the mesothoracic scutum with the plate that Burmeister and Lowne call the meta- sternum. How can this be? There is only one answer. ‘This plate is not, as they regard it, metathoracic*.
In addition to its muscular connexion with the mesothoracic scutum, I would suggest the following reasons for regarding it as the mesothoracic epimeron. We have seen from Mr. Lowne’s account (op. cit.) that the prothoracic sternum sends out posterior to the coxe two “cornua,” which, passing outwards, expand into small plates that surround the acetabula of the fore legs and reach as far as the anterior spiracles (see Pl. I. fig. 2), the condyles, and the lateral plates of the prothorax. Ina perfectly similar manner it appears to me that the mesothoracic epimera, if I may be allowed so to call them, originate from the posterior extremity of the sternum of that segment, and, passing outwards, surround the acetabula of the intermediate legs, and are there brought into contact with the spiracles, the sternum of the segment, and the posterior lateral plates of Lowne, Audouin’s episterna. It is a character of Audouin’s epimeron that it is always in connexion with the coxa, and articulates with the sternum and episternum of the segment. Again, the posterior mass of vertical muscles, the costali dorsaux of Chabrier, unites the posterior portion of the mesothoracic scutum with Lowne’s lateral plate of the metathorax just above the posterior haltere. This, too, appears inconsistent with the rule of muscular structure adverted to; and I must regard this plate also as part of the mesothorax, though I am unable to identify it certainly with any of Audouin’s pieces; I think it probably forms part of the postscutellum, together with the central portion between the bases of the halteres.
Thus it appears to me that the analogy of other insects, the
* Anted p. 13. ;
+ Cyclop. of Anat. and Physiol., “Insecta,” p. 48, for which reason also I re- gard the above-mentioned cornua as the epimera of the prothorax, as stated
anted p. 14. 3*
28 MR. A. HAMMOND ON THE
phenomena of development, and the study of the muscular system, all combine to show that the thorax of the Diptera as illustrated in this insect is almost exclusively mesothoracic. Nothing is left of the metathorax except the halteres, a narrow strip possibly along the posterior edge of the mesothoracic epimera, the coxe, and the entosternum of the segment, to which must be added the posterior surface of the mesophragma, formed, as in many other cases, by the inversion and adherence together of the two layers of integument of the postscutellum of the one segment and the prescutum of the other. The only remnants of the metathoracic muscles which exist are two thin slips which, originating at the posterior surface of the mesophragma close to the halteres, pass downward and forward, and are inserted in the entosternum of the metathorax. The fact of their being so inserted proves that they are metathoracic muscles. The further fact of their originating on the posterior surface of the mesophragma again shows that that posterior surface is metathoracic, as just stated, and that the cavity of the metathorax, if cavity it can be called, is posterior to this surface and continuous with that of the abdomen. Again, if a further proof be sought, it may be found in the projection into that cavity of the two slender apodemes of the halteres before referred to.
Lastly, I may add a few words on the light the muscular system throws on the boundaries of the prothorax. We have seen how the longitudinal muscles of the mesothorax avoid the humeri. I would now point out, from Pl. I. figs. 9 & 11, that the vertical muscles do the same, not being sufficiently advanced anteriorly to reach them; while, on the other hand, a muscle of considerable size, which, passing as it does to the anterior coxa, must, I submit, be regarded as prothoracic, takes its origin from the same parts (see Pl. I. fig. 12). Furthermore, that the condyles form part of the prothoracic segment *, I must conclude from the observation that a pair of muscles connect their interior surfaces with the rami which represent the entosternum 7 at the posterior inferior margin of the segment behind the cox; they represent pro- bably the anterior lateral processes of the prosternum of the Coleoptera.
I shall only further remark that truth is frequently only to be
* Anted, pp. 11 and 14, t Anted, p. 15.
THORAX OF THE BLOW-FLY. 29
arrived at through a series of errors, and that I can scarcely hope that all my observations will prove exceptions to the general rule.
DESCRIPTION OF THE PLATES. All the illustrations are necessarily much magnified.
The parts of the thorax are designated in accordance with my own view of their relations, except where indicated in brackets, and are lettered the same throughout the series of figures, viz.:—.
h. The humerus. prs. The prescutum of the mesothorax.
sem. The scutum of the mesothorax.
sem’. . ne metathorax (not found in the Blow-fly). sel. The scutellum of the mesothorax. sel. 5 as metathorax (not found in the Blow-fly).
con. Lateral processes of the prosternum (Lowne’s condyles).
epis. The lateral plates (episterna) of the prothorax.
sp. The anterior (prothoracic) spiracle.
sp'. The posterior (mesothoracic) spiracle.
sp*. The spiracle of the fifth segment.
cox, cox', cox’. The anterior, intermediate, and posterior coxe.
par. The parapteron (Lowne’s anterior lateral plate of the mesothorax).
epim. The epimeron of the prothorax (Lowne’s cornua).
st. The sternum of the prothorax.
st’. 3 5 mesothorax.
epis'. The episternum of the mesothorax (Lowne’s posterior lateral plate).
zw. Uncertain (Lowne’s lateral plate of the metathorax).
epim'. The epimeron of the mesothorax (Lowne’s metasternum).
ps. The postscutellum of the mesothorax (in Pl. I, Lowne’s dorsal plate of the metathorax).
ps'. The postscutellum of the metathorax (not found in the Blow-fly).
lm and vm. Longitudinal and vertical muscles of the mesothorax of the Blow- fly (Pl. I.).
mes. Mesothorax (Pl. II.); mez. Metathorax (Pl. IT.).
%. The dorsal plate of the fifth segment (Pl. IT.).
m. The longitudinal muscles of the mesothorax (Pl. IT.). m'. . 5) metathorax (Pl. II.).
Puate I.
Fig. 1. Dorsal surface of thorax of Blow-fly. 2, Ventral surface of ditto: f, the cephalothoracie foramen; ae, aceta- bulum of fore leg; hal, the haltere. 3. Entosterna of meso- and metathorax, side view, 4, The same, from above.
30 Fig. 5.
12.
13.
Fig. iL
ON THE THORAX OF THE BLOW-FLY.
Anterior view of prothorax ; p7, pronotum.
. Lateral view of thorax. . Posterior view of ditto: ps, postscutellum of the mesothorax; mph,
mesophragma formed by the united postscutellum of the mesothorax and the preescutum of the metathoraxt; al, alulet; mm, metatho- racic muscles proceeding to metathoracic entosternum ; ap, apodeme of haltere; z, narrow margin, probably remains of lateral plate of metathorax ; 7, line of junction of thorax and abdomen.
. Longitudinal vertical section of thorax in the mesial line, showing lon-
gitudinal muscles: prov, the proventriculus followed by the chyle- stomach.
. The same, with the longitudinal muscles removed, showing :—vm', wm?,
vm*, the vertical muscles ; 7, prothoracic muscle inserted in the fore coxa; mm, metathoracic muscle to entosternum.
. Transverse vertical section of thorax, showing muscles. . Horizontal longitudinal section of ditto.
Internal view of a portion of the thoracic cavity, showing :—pm, the muscle of the fore coxa; m*, small muscles connected with the wing beneath the parapteron. A strong process, g, of the prescutum is seen to bridge across the humerus without touching it.
The pupa of the Blow-fly: 0, the compound eyes ; pa, the prothoracic dorsal appendages.
Prats IT. Pupa of Crane-fly. Anterior portion, showing :—pa, the prothoracic appendages; mes, the posterior portion of the mesothorax (upon removing the integument at this part, the postscutellum of the me-
sothorax (ps, fig. 2) of the imago is revealed) ; met, the metathorax ; w, w', the anterior and posterior wing-cases.
- The thorax of the Crane-fly. The plate, ps, between the halteres, cor-
responding to the posterior wall of the thorax of the Blow-fiy, is shown to be mesothoracic, @. e. the mesothoracic postscutellum as it is developed beneath the mesothoracic integument of the pupa.
3 & 4. The anterior and posterior wing-cases of the pupa of the Crane-
5.
6.
fly. The haltere is shown in course of development within the latter. Longitudinal vertical section ‘of the thorax of the Humble-Bee: ps, the
postscutellum of the mesothorax, to which the muscles, 7, are attached. The thorax of the same, showing the reduced extent of the metathorax :
col, the collar ; a, its posterior angle; sp*, spiracle of fifth segment.
7 & 8. Figures adopted from Packard, showing the two stages in the deve-
a 10.
lopment of the pupa of the Humble-Bee. In the latter the thoracico- abdominal constriction is seen to include the fifth segment (2) with the thorax: sp*, the spiracle of the fifth segment.
The thorax of Liparis salicis.
Longitudinal vertical section of the thorax of Ziparis salicis: parts the same as in fig. 5.
+ Consult antet, p. 28.
ON THE INSTINCTS AND EMOTIONS IN FISH. bl
Fig. 11. Ditto of Acrida viridissima, showing two sets of longitudinal muscles.
12. The marginal disks of the Crane-fly attached to the nerve-centres: U', 7’, 0", those of the legs; pa, that of the prothoracic appendage ; w, w', those of the wings and halteres.
13. Thorax of Goerius olens, showing the dorsal plate of the fifth segment, z, attached thereto and separated from the succeeding abdominal ones: ps', the postscutellum of the metathorax.
14. Vertical thoracic muscles of Zishna grandis, showing a distinct repe- tition, 1 2 3 4, 1 2 3 4, in each segment.
15. The subtriangular metaphragma of Rhizotrogus solstitialis formed by the postscutellum of the segment, for comparison with the postscutel- lum in fig. 13.
Instincts and Emotions in Fish. By Francis Day, F.L.S.
[Read November 6, 1879.]
Durtine the last few years the instincts of brutes have received much attention from biologists, while those of fishes have been generally passed over. Some naturalists have not hesitated to assert that the lives of the finny tribes are destitute of the joys and sorrows generally appertaining to vertebrate animals, attri- buting to them an almost vegetative existence. In a work lately published in this country, Cuvier’s low estimate of their intelli- gence has again been adopted in its entirety, although during the course of this century much information has accumulated point- ing in an opposite direction. Irrespective of this, the ancients must have had a higher opinion of the finny tribes than the authors of the present time, if we are to judge from the attributes they accorded to fish.
But returning to half a century since, we find that Cuvier had no very exalted opinion of the intellect of fishes, considering that among all the vertebrate animals they show the least signs of sensibility, which of course might be expected, as they are the lowest division. Nearly or quite destitute of any voice, with im- movable eyes and a fixed osseous face, their physiognomy has no play, their emotions no expression, only capable of hearing the loudest sounds, for, condemned to reside in an empire of silence, they have but small occasion for the sense of hearing. No tear
32 MR. F. DAY ON THE
moistens, no eyelid shelters or wipes the surface of the eye, which is but an indifferent representative of that organ as existing in the superior classes of animals. Delicate sense of taste is said to be wanting, and that of smell to be but small; while feeling on the surface of their bodies is almost obliterated, due to the interposition of scales, and, in some species, even their very lips are converted to the hardness and insensibility of bone. To pursue their prey or escape an enemy is the constant occupation of their lives, determines their place of abode, and is the principal object of the diversities of form among them. Their sexual emo- tions, cold as their own blood, indicate merely individual wants. With scarcely an exception, fish do not construct a nest; they neither feed nor defend their offspring. The inhabitant of the waters knows no attachments, has no language, no affections ; feelings of conjugality and paternity are not acknowledged by him ; ignorant of the art of constructing an asylum, in danger he seeks shelter among rocks or in the darkness of profound depths: his life is silent and monotonous.
What a gloomy picture is here sketched out respecting fishes ! Eager in the pursuit of prey in order to satisfy the cravings of hunger, or terrified at the approach of danger, their lives, which are said to be silent, monotonous, and joyless, would appear to be scarcely worth preserving ; death itself, one would imagine, must be a happy release from a burdensome existence. But fishermen are well aware that the finny tribes are as eager to escape from danger, or avoid capture, as are the inhabitants of the earth or the frequenters of the air, which compels us to question whether their lives are so joyless as has been represented—if anger or affection are really among their unknown passions.
I will first observe upon the means possessed by fishes enabling them to demonstrate their emotions. First, we find that they are capable of erecting their dermal appendages, as scales or fin-rays, under the influence of anger or terror, similarly as feathers or hairs are erected in birds and mammals. But special expressions, as those of joy, pain, astonishment, &c., we could hardly anticipate being so well marked in fishes as in some of the superior grades of animals, in which the play of the features frequently affords an insight into their internal motions. Eyes without movable eye- lids, cheeks encased with bony plates or covered with hard scales, are scarcely suitable for smiling or developing into a laugh. Ex-
INSTINCTS AND EMOTIONS IN FISH. 30
ternal ears likewise are wanting. Still we perceive one very distinct expression in this vertebrate class which is absent, or but slightly developed, in many of the higher animals, namely, change of colour*. Most of us are aware that when a fish sickens its brilliant tints become less and less, or even entirely fade away, while the same result may follow being vanquished by a foe. But when in good health and residing in suitable localities, especially during the breeding-season, their colours become vivid, and even a temporary accession of anger may cause a similar result.
The first subject for investigation is, Are the finny tribes desti- tute of affections? Here I purpose inquiring whether fish are monogamous or polygamous, whether they show signs of affec- tion to their companions, if they construct nests, guard their nests or eggs, protect their offspring, and, lastly, if they are ever known to exhibit traits of affection for human beings. In some parts of the world, more especially in fresh waters, we have monogamous as well as polygamous fishes—the former, as a rule, not depositing so many eggs as the latter, probably for two reasons, (1) that they breed more frequently, and (2) that they generally protect their offspring. The Gouramy (Osphromenus olfax) at the Mauritius commences breeding at six months of age, while their fecundity is astonishing. During the breeding- season they frequent the sides of tanks, where shelter is afforded them by the grasses and weeds growing in the water, or several days they are very active, passing in and out of their grassy cover, and in some places thickening it by entangling all trailing shoots, and forming what is generaily considered the spot under which the ova are deposited?. They continue to watch this place with
* Tt is not here held that change of colour is always due to emotional sensations. Thus Professor Agassiz observes that in young Plewronectoids the embryos were very sensitive to light, both sides changing colour rapidly at will. He considers that as soon as the two eyes become situated exclusively on one side of the head, the nerve controlling the colour-cells, of what has now become the eyeless side, becomes gradually unable to act, consequently the under or blind side becomes colourless. It seems to be an almost invariable fact that the under surface in fish is less vividly coloured than the upper surface, and that such is occasioned by the influence of light ; but whether such is entirely due to the action of the optic nerve is open to grave doubt, for were it so, all blind fish would be colourless; and here, again, we must distinguish between those which are sightless owing to living in dark caves, and others which are 80 consequent upon accidental loss of vision in their embryonic stage.
t On nest-building fishes, see Martens, Zool. Gart. 1872, pp. 107-111.
34 MR. F. DAY ON THE
the greatest vigilance, driving away any interloping fish; and at the end of a month numerous fry appear, over which the old Gouramies keep guard many days*. M. Carbonnier, who has studied the habits of the Chinese Butterfly-fish (Macropodus) in his private aquarium in Paris, where he had some in confinement, observed? that the male constructs a nest of froth of considerable size, 15 to 18 centimetres horizontal diameter, and 10 to 12 high. He prepares the bubbles in the air (which he sucks in and then expels), strengthening them with mucous matter from his mouth, and brings them into the nestt. Sometimes the buccal secretion will fail him, whereupon he goes to the bottom in search of some conferve, which he sucks and bites for a little in order to stimu- late the act of secretion. The nest prepared, the female is in- duced to enter. Not less curious is the way in which the male brings the eggs from the bottom into the nest. He appears unable to carry them up in his mouth; instead of this, he first swallows an abundant supply of air, then descending, he places himself beneath the eggs, and suddenly, by a violent contraction of the muscles in the interior of his mouth and pharynx, he exhales the air which he had accumulated by the gills. This air, finely divided, partly by the lamelle and fringes of the gills, es- capes in the form of two jets of veritable gaseous powder, which envelops the eggs and raises them to the surface. In this manceuvre the MWacropodus entirely disappeared in a kind of air- mist, and when this had dissipated he reappeared with a multitude of air-bubbles like little pearls clinging all over his body.
In Asia there are several species of Snake-headed or Walking- fishes (Ophiocephalus). 'The male of the common striped form, O. striatus§, constructs a nest with his tail among the vegetation at the side of tanks, biting off the ends of the weeds that grow in the water. Here the ova are deposited, the male keeping guard ; but should he be killed or captured, the vacant post is filled by his partner. It is a curious sight to see them with their fry swim- ming along near the surface of the water, the latter generally
* General Hardwicke, Zool. Journal, iy. 1829, p. 309.
+ Bulletin de la Société d’Acclimatation, Paris, 1872.
{ The same fact has been observed of the Gasterosteus aculeatus by Mr. Mabel, the Curator of the Weston-super-Mare Museum.
§ Pristolepis malabaricus, which is not amphibious, constructs a nest accord- ing to Mr, Thomas.
_ INSTINCTS AND EMOTIONS IN FISH, 35
going in single file above them. The parents are very fierce at this period, and defend their offspring with great courage*. I have likewise personally witnessed in Canara the young of the orange Walking-fish, O. awrantiacus, swimming about with their parents, by whom they are protected, according to native fisher- men, until they are able to shift for themselves, when they are driven away by their progenitors. The fishes enumerated as monogamous, viz. Osphromenus, Macropodus, and Ophiocephalus, are all amphibious Acanthopterygians and inhabitants of Asia. I will now pass on to examples taken from other localities.
Pennantt remarks that the river Bullhead (Cottus gobio) de- posits ity spawn in a hole it forms in the gravel, and quits it with ereat reluctance. We are told of a Russian fish, Bitshkit, that it is one of the most remarkable of those in the Black Sea, and always occasions fever in whoever eat it, while it builds for its young a nest like a bird. The male and female unite their cares in its construction, gathering seeds and soft seaweeds, and de- positing them in small holes on the shore. In this the female not only lays her eggs, but watches them carefully like a hen; and when the little ones are hatched, they remain near the mother till they are sufficiently grown to venture forth alone into the world of waters.
In South America two species of monogamous fish, termed “Hassar”’ and also “ Hardback,” of the genus Callichthys, have been observed to construct nests—the flat-headed form (C. asper) of leaves, and the round-headed kind (C. punctatus) of grass; in these they deposit their eggs, which they carefully cover, and both sexes watch and defend them till the young come forth. The late Dr. Jerdon§ remarked of the beautiful little Htroplus maculatus, an inhabitant of the streams of Southern India and Ceylon, that the eggs, which were not very numerous, were deposited in the ~ mud at the bottom of a stream; and when hatched, both parents guarded their young for many days, vigorously attacking any large fish that passed near them. It is evident, in this case, that they must have remained in the vicinity of their eggs and watched over them until the young came forth. The Lump-sucker, Cyclo-
* Col. Puckle, Report on the Fishes of Bangalor. t Brit. Zool. iii. 1776, p. 216
} Koht’s ‘ Russia.’
§ Madras Journ. Lit. and Sc. 1849, p. 148.
36 MR. F. DAY ON THE
pterus lumpus, is, according to Yarrell and others, a fish that shows attachment for its eggs. At the spawning-time the female precedes and deposits her ova among the larger alge and in fis- sures of the rocks; the male shortly follows and fructifies the eges, adhering so closely to the mass of roe that the impression is left upon the hollow surface of the shield formed by the ventrals, after which he keeps watch over the deposited ova and guards them from every foe with the utmost courage. If driven from the spot by man he does not go far, but is continually looking back, and in a short time returns. Dr. Johnston observes that the fishermen in Berwickshire believe that the male covers the spawn and remains covering or near it until the ova are hatched, and that the young soon after birth fix themselves to the sides and on to the back of their male parent, who sails, thus loaded, to deeper and more safe retreats.
Agassiz remarks* that while examining the marine products of the Sargasso Sea, Mr. Mansfield picked up and brought to him a round mass of sargassum, about the size of the two fists, rolled up together. The whole consisted, to all appearance, of nothing but gulf-weed, the branches and leaves of which were, however, evi- dently knit together, and not merely balled into a roundish mass. The elastic threads which held the gulf-weed together were beaded at intervals, sometimes two or three beads being close together, or a branch of them hanging from the cluster of threads. This nest was full of eggs scattered throughout the mass and not placed together in a cavity. It was evidently the work of the Chironectes. This rocking fish-cradle is carried along as an un- dying arbour, affording at the same time protection and after- wards food for its living freight. It is suggested that they must have used their peculiar pectoral fins when constructing this elaborate nest.
The well-known Tinker or ten-spined Stickleback, Gasterosteus pungitius, is one of our indigenous fish which constructs a nest. On May Ist, 1864, a malet was placed in a well-established aqua- rium of moderate size, and in which, after three days, two ripe females were added. Their presence at once roused him into activity, and he soon began to build a nest of bits of dirt and dead fibre and of growing confervoid filaments ,upon a jutting point of
* Silliman’s American Journal, Feb. 1872. t Ransom, Ann. & Mag. Nat. Hist. 1865, xvi. p. 449.
INSTINCTS AND EMOTIONS IN FISH. 37
rock among some interlacing branches of Myriophyllum spicatum— all the time, however, frequently interrupting his labours to pay his addresses to the females. This was done in most vigorous fashion, he swimming, by a series of little jerks, near and about the female, even pushing against her with open mouth, but usually not biting. After a little coquetting she responds and follows him, swimming just above him as he leads the way to the nest. When there, the male commences to flirt—he seems unaware of its situation, will not swim to the right spot, and the female, after a few ineffectual attempts to find the proper passage into it, turns tail to swim away, but is then viciously pursued by the male. When he first courts the female, if she, not being ready, does not soon respond, he seems quickly to lose his temper, and, attacking her with great apparent fury, drives her to seek shelter in some crevice or dark corner. ‘The coquetting of the male near the nest, which seems due to the fact that he really has not quite finished it, at length terminates by his pushing his head well into the entrance of the nest, while the female closely follows him, placing herself above him, and apparently much excited. As he with- draws she passes into the nest, and pushes quite through it, after a very brief delay, during which she deposits her ova. The male now fertilizes the eggs and drives the female away to a safe distance; then, after patting down the nest, he proceeds in search of another female. The nest is built and the ova deposited in about twenty- four hours. The male continued to watch it day and night, and during the light hours he also continually added to the nest.
The marine “15-spined Stickleback,” Gasterosteus spinachia, affords another instance of nest-constructing fishes. The places selected for their nests are usually harbours or some sheltered spots to where pure sea-water reaches. ‘The fish either find growing or even collect some of the softer kinds of green or red seaweed, and join them with so much of the coralline tufts (Janie) growing on the rock as will serve the purpose of affording firm- ness to the structure, and constitute a pear-shaped mass five or six inches long, and about as stout as a man’s fist. A thread, which is elastic and resembles silk, is employed for the purpose of binding the materials together ; under a magnifier it appears to consist of several strands connected by a gluey substance, which hardens by exposure to the water. In one instance the situation selected was the loose end of a rope, from which the separated strands hung at about a yard below the surface in five or six
38 MR. F. DAY ON THE
fathoms of water, to which the materials must haye been con- veyed at least thirty feet. The nest, which was of the usual construction, was matted together in a hollow formed of the untwisted strands of the rope, and in it were deposited the ova in the usual way. It was watched over by the parent, who did not appear to quit his station ; still imstances have been ob- served when more than one watcher was present.. When the guardian is compelled to retreat, owing to a receding tide, he returns again with the first suitable wave; and in three or four weeks the young emerge. So intent is this fish on the object over which he keeps guard, that at this time he may be easily captured, but he resents all interference with the nest; if the ova are exposed, he at once repairs the breach by dragging fresh materials into a position by which they are again concealed and protected*.
Not only will some fishes protect their nests in which are deposited the ova, but forms which do not construct any receptacle for their eggs have interesting modes of protecting them or removing them from localities where they may be exposed to danger. The Siluroid, or scaleless, also termed Sheat-fishes (Stlurid@), although almost unknown in the colder regions of the North, become numerous as the tropics are ap- proached, some being marine forms, others restricted to the fresh waters. These fishes delight in muddy localities, and seek their food by means of feelers placed around the mouth, as well as by means of hearing, their air-bladder forming an acoustic organ. The marine and estuary genera of which the group Ariwna is com- posed, all deposit large eggs from 0:5 to 0'6 of an inch in diameter ; and while examining the fishes along the western coast of India, I found many of the males of this group with from fifteen to twenty of these large eggs in their mouths. Some of these eggs were in an early stage of development, others ready for hatching, while one example contained a young fry hatched, but having the yelk- bag still adherent. They filled the cavity of the mouth and pharynx of these male fishes. Whether the male carries these eges about in his mouth until they are hatched, or merely removes them from some spot when danger is imminent, of course may be open to question ; but it is a significant fact that in none of the
* Couch, Brit. Fishes, i. p. 182. M. Gerbe (Rev. et Mag. Zool. xvi. pp. 255, 278, 337, 1865) observes that fishes of the genus Crenilabrus build a nest of seaweed ; here the ova are deposited; both sexes assist in its construction,
. INSTINCTS AND EMOTIONS IN FISH. 39
examples which I dissected could I find a trace of food through- out the intestines of the males who had been engaged in this in- teresting occupation*. The same phenomenon was observed in two examples of Arius fissus which came from Cayenne, and were presented to the British Museum+, and by Dr. Hensel in the Brazilian Arius Commersonii. A fish from Lake Tiberias, Chromis paterfamilias, has been describedt, the male of which carries the eggs in the buccal cavity, the young even remaining there some time after they have been hatched. It has been remarked of the Siluroid genus Aspredo, that they take care of their progeny, and the females possess appendages for the purpose of keeping the eggs attached to the belly of the mother§. Some fishes, as the Salmon, the Trout, and the Shad, have been known to discontinue feeding during the breeding-season||._ . Among Batrachians we also see that the males may carry the eggs until hatched: thus, in Rhino- derma Darwinii, the males have an extraordinary brood-sac deve- loped as a pouch from the throat, and extending over a great portion of the ventral surface of the animal. In this cavity a number of living tadpoles have been observed by the Spanish naturalist Jimenez de la Espada{.
Fish, however, have other modes of showing solicitude for the welfare of their eggs, some of which I have already mentioned; but a few more instances perhaps will not be considered superfluous. In some interesting'observations respecting the construction of the nest and the habits of the “ Three-spined Stickleback,” Gaster- osteus aculeatus**, it has been remarked that after the depo- sition of the eggs the nest was opened more to the action of the water, and the vibratory motion of the body of the male fish, hovering over its surface, caused a current of water to be propelled
* Day, ‘ Fishes of India,’ p. 456.
t Lortet, Compt. Rend. 1875, Ixxxi. p. 1196.
{ Giinther, Catal. v. p. 173.
§ L. c. p. 268.
|| Max Weber, Arch. f. Nat. (2) xlii. p. 169.
{| Sprengel, Zeitschrift fiir wissensch. Zool. vol. xxiv. part 4 (1877).
** The Gasterosteus aculeatus, says Baker, Phil. Trans. Roy. Soc., seek, out and destroy all the young fry that come in their way, which are pursued with the utmost eagerness and swallowed down without distinction provided they are not too large. He continues that one did (on 4th of May) “devour in five hours’ time seventy-four young dace, which were about + of an inch long, and of the thickness of a horsehair; two days after it swallowed sixty-two, and would, I am persuaded, have eaten as many every day could I have procured them for it.”
40 MR. F. DAY ON THE
across the surface of the ova, which action was repeated almost continuously. After about ten days the nest was destroyed and the materials removed ; and now were seen the minute fry flutter- ing upwards here and there, by a movement half swimming, half leaping, and then falling rapidly again upon or between the clear pebbles of the shingle bottom. This arose from their having the remainder of the yelk still attached to their body, which, acting as a weight, caused them to sink the moment the swimming effort had ceased. Around, across, and in every direction the male fish, as the guardian, continually moved. Now his labours became more arduous and his vigilance was taxed to the utmost extreme, for the other fish (two Tench and a gold Carp), some twenty times larger than himself, so soon as they perceived the young fry in motion, continuously used their utmost endeavours to snap them up. The courage of the little Stickleback was now put to its severest test ; but, nothing daunted, he drove them all off, seizing their fins and striking with all his strength at their heads and at their eyes. His care of the young brood when encumbered with the yelk was very extraordinary ; and as this was gradually absorbed and they gained strength, their attempts to swim carried them to a greater distance from the parent fish; his vigilance, however, seemed everywhere, and if they rose by the action of their fins above a certain height from the shingle bottom, or flitted beyond a given distance from the nest, they were imme- diately seized in his mouth, brought back, and gently puffed or jetted into their place again*. The same care of the young, bringing them back to their nest up till about the sixth day after hatching, has been remarked by Dr. Ransom in the 10-spined Stickleback, G. pungitius.
The usual time for the Lamprey, Petromyzon fluviatilis, leaving the sea, which it is annually seen to do, in order to spawn, is about the beginning of spring ; and after a stay of a few months it returns again to the ocean. Their preparation for spawning is very peculiar: their manner is to make holes in the gravelly bottoms of rivers; and on this occasion their sucking power is particularly noticeable, for if they meet with a stone of conside- rable size, they will remove it and throw it out. Their young are produced from eggs; the female remains near the place where they are excluded, and continues with them till they come forth.
* Warrington, ‘‘ On the Habits of the Stickleback,” Ann. & Mag. Nat. Hist 1855, xvi. p. 830.
INSTINCTS AND EMOTIONS IN FISH. AL
She is often seen with her whole family playing about her, and after some time she conducts them in triumph to the ocean. (Buffon.) _
Among the Lophobranchiate order of fish, or those in which the gills consist of small rounded tufts attached to the branchial arches, and which are represented by the Pipe- and Horse-fishes of the British seas, we find that in most of the species the males perform the function of hatching the eggs, which for that purpose are deposited up, to the time of the evolution of the young, either be- tween the ventrals (in the genus Solenostomus), or in tail-pouches (in Hippocampus), or in pouches on the breast and belly Gn Dory- rhamphus), or in rows on the breast and belly (in Werophis), and are thus carried about by the fish*. M. Risso notices the great attachment of the adult Pipe-fish to their young, and this pouch probably serves as a place of shelter to which the young ones retreat in case of danger. I have been assured by fishermen that if the young were shaken out of the pouch into the water over the side of the boat, they did not swim away, but when the parent fish was held in the water in a favourable position the young would again enter the pouch.
M. Carbonnier has recorded how the male of the curiously
srotesque Telescope-fish, a variety of Carassius auratus, Linn., acts as accoucheur to the female. Three males pursued one female which was heavy with spawn, and rolled her like a ball upon the ground for a distance of several metres, and continued this process without rest or relaxation for two days, until the ex- -hausted female, who had been unable to recover her equilibrium for a moment, had at last evacuated all her ova ¢. - That adult fish are capable of feeling affection one for another would seem to be well established: thus Jesse relates how he once captured a female Pike (sow luciws) during the breeding- season, and that nothing could drive away the male from the spot at which he had perceived his partner slowly disappear, and whom he had followed to the edge of the water.
Mr. Arderon§ gave an account of how he tamed a Dace, which would lie close to the glass watching its master ; and subsequently
* Kaup, Catal. Lopho, Fish in Brit. Mus. 1856, p. i. + Yarrell, Brit. Fishes, 2nd ed. ii. p. 436. ¢ Compt. Rend. Noy. 4th, 1872, p. 1127. § Phil. Trans. Royal Society, 1747. LINN. JOU RN,—ZOOLOGY, VOL. XV, 4
42 MR. F. DAY ON TIE
how he kept two Rufts(Acerina cernua) in an aquarium, where they became very much attached to one another. He gave one away, when the other became so miserable that it would not eat, and this continued for nearly three weeks. Fearing his remaining fish might die, he sent for its former companion, and on the two meeting they became quite happyagain. Jesse gives a similar account of two gold Carp. Mr. Oliver has recorded how a Trout was placed in a well at Dumbarton Castle, and died in 1809, after having inhabited that locality twenty-eight years. It had become so tame that it would receive its food from the hands of the soldiers. Lacépéde relates how some fish, which had been kept in the basin of the Tuileries for upwards of a century, would come when they were called by their names ; while in many parts of Germany, Trout, Carp, and Tench were summoned to their food by the ringing ofa bell. “ Ata passage-place near to the city of Kandy, the fish formerly have been nourished and fed by the king’s order, to keep them there for his majesty’s pleasure; whither, having been used to be thus pro- vided for, notwithstanding floods and strong streams, they will still resort, and are so tame that I have seen them eat out of men’s hands”’*. Ellis, in his ‘ Polynesian Researches,’ speaks of a native chief of the island of Hawaii who had brought eels to that degree of tameness that he could call them from their retreat with the shrill sound of a whistle. Pliny also remarks that eels may be tamed so completely that they will eat out of your hand. At Erritara Carvee, in the Cochin state of Malabar, is an umbalum situated on the bank of the deep river, which is 500 yards wide, where the fish receive a supply of food every week ; here hundreds of Carp (Barbus) flock up to obtain rice from passers- by, and are so tame that they will take food from a person’s hand f. At many temples in India fishes are called to receive food by means of ringing bells or by musical sounds. Lieutenant Conolly remarks upon seeing numerous fishes coming to the ghaut at Sidhnath to be fed when called; and on expressing our admiration of the size of the fish, “‘ Wait,” said a bystander, “ until you have seen‘ Raghu.’” “ The Brahmin called out his name ina peculiar tone of voice, but he would not hear. I threw in handful after handful of ottah (flour) with the same success, and was just leaving the ghaut, despairing and doubting, when a loud plunge startled me. I thought somebody had jumped off the bastion of the * Knox, Ceylon, 1681, p. 56. t Day, ‘Land of Permauls,’ 1863, p. 502,
INSTINCTS AND EMOTIONS IN FISH. 43
ghaut into the river, but was soon undeceived by the general shout of ‘ Raghu,’ ‘ Raghu,’ and by the fishes large and small darting away in every direction. Raghu made two or three plunges, but was so quick in his motions that I was unable to guess at his species” *. In Burma, in the Irrawaddi river, there are fish so tame as to come up to the sides of the boat, and even allow themselves to be handled. The Fakeers of the place call them together, but they are not much disposed to come for mere calling, seeming to require more substantial proof of being wanted in the shape of food; they are found in still waters in a small bay, which is closed up still more from the influence of the stream by a round island constructed superficially on a rocky base, and on which the pagodas are built. They resemble a good deal the Gooroo mas, a Siluroid of Assam, but have no large teeth as it has (most probably the fish was a Fifa). They are very greedy, of a bluish-grey colour, occasionally inclining to red (Griffith, p- 104). Carew, in Cornwall, is said to have called his Grey
Mullet together by making a noise like chopping with a cleaver ; and Sir Joseph Banks collected his fish by means of sounding a bell.
The manifestations of anger are well described in the accounts we possess of the Fighting Fishes of Siam. After remarking on the cock-fights of that country, Sw J. Browning adds, there is a little bellicose fish, too, which attacks its fellow with great ferocity, bristling its fins and exhibiting the most intense excite- ment ; one of these, seeing its reflection in a glass, will violently advance head foremost against the shadow. Dr. Cantor+t ob- serves, respecting this fish, Macropodus pugnaa, that when it is in a state of quiet, with the fins at rest, the dull colours present nothing remarkable. Butif two are brought within sight of each other, or if one sees its own image in a looking-glass, the little creature becomes suddenly excited, the raised fins and the whole body shine with metallic colours of dazzling beauty, while the projected gill-membranes, waving like a black frill round the throat, add something grotesque to the general appearance. In this state it makes repeated darts at its real or reflected antago- nist; but both, when taken out of each other’s sight, instantly
* Conolly, “Obs. on past and present Condition of Onjein,” J. As. Soc. Beng,
vi. p. 820. + ‘Kingdom and People of Siam, p. 155. t ‘Catal. Malay. Fish.’ 1850, p. 87.
4A. MR. F. DAY ON THE
become quiet. When a few examples of the three-spined Stickle- back (Gasterosteus aculeatus) are first turned into a tub of water, they swim about in a shoal, apparently exploring their new habi- tation. Suddenly one will take possession of a particular corner of the tub, or, as will sometimes happen, of the bottom, and will instantly commence an attack upon his companions; and if any one of them ventures to oppose his sway, a regular and most furious battle ensues; the two combatants swim round and round each other with the greatest rapidity, biting and endea- vouring to pierce each other with their spines, which on these occasions are projected. I have witnessed a battle of this sort which lasted several minutes before either would give way; and when one does submit, imagination can hardly conceive the vin- dictive fury of the conqueror, who, in the most persevering and unrelenting way, chases his rival from one part of the tub to another, until fairly exhausted with fatigue. I have occasionally known three or four parts of the tub taken possession of by as many other little tyrants, who guard their territories with the strictest vigilance; and the slightest invasion invariably brings on a battle. These are the habits of the male fish alone*. After a fight between two examples a strange alteration takes place almost immediately in the defeated party: his gallant bearing forsakes him, his gay colours fade away, he becomes again speckled and ugly, and hides his disgrace among his peaceable companions, who occupy together that part of the tub which their tyrants have not taken possession of ; he is, moreover, for some time the con- stant object of his conqueror’s persecutiont. We here perceive how the disgrace of defeat affects the spirits of the vanquished, and this reacting on the health, causes his brilliant hues to fade away. The conqueror, on the other hand, exulting in his victory, becomes more resplendent : he does not forget his former triumph, and considers it no disgrace to occasionally lord it over his fallen foe. Under the influence of fear, the Indian Climbing-Perch (Anabas scandens) not only erects its spiny-rayed fins, but also its scales, even down to those situated at the base of its caudal fin. Every one who possesses an aquarium knows how, on a spiny- rayed fish being frightened or angry, he at once elevates his fins. The Diodon has several means of defence. It can give a severe
* Mag. Nat. Hist. iii. p. 330. t Couch, ‘ British Fishes,’ i. p. 172.
INSTINCTS AND EMOTIONS IN FISH. 45
bite ; while by inflating its body, the papillze with which the skin is covered become erect and pointed*. Mr. Whitmee observes :— “T have seen a Balistes (File-fish) swim rapidly past its anta- gonist and graze its side with its file-like lateral spines.”’ “I once tried to catch a Letrodon nigripunctatus which was in my aqua- rium, when it inflated itself and elevated the fine spines with which the body was covered, and which were previously buried in its loose and flabby skin. This of course was under the influ- ence of fear’’t. Siluroids are furnished with more than one mode of attack. Inthe Ohio exists a species of this family, in which the first dorsal ray is formed of a very strong and short spine, which the animal uses to kill others of a smaller size ; for this purpose it gets beneath the fish it intends to attack, and then sud- denly rises and wounds it repeatedly in the belly. There is ano- ther curious form in Burma (Macrones leucophasis) said to swim with its belly uppermost, therefore termed by the Burmese the “Topsy-turvey fish;’’ it probably ascends to above its prey, Lately I have been favoured with the sight of a drawing of a fish, Bagrus, existing in the Nile which is observed, while in an aqua- rium, to swim ina similar manner. Siluroids likewise erect the osseous and armed spines of their dorsal and pectoral fins. Some years since, while stationed at Madras, I obtained several live ex- amples of these fishes, Macrones vittatus, termed the Fiddler-fish in Mysore. I touched one which was lying on some wet grass ; it became very irate, erecting its armed spines and emitting a sound resembling the buzzing of a bee, evidently a sign of anger or terror. Having placed some small Carp in an aquarium con- taining one of these fish, it rushed at a small example, seized it by the middle of its back, and shook it as a dog kills a rat: at this time its barbels were stiffened out laterally like a cat’s whiskers. Couch observes of the Stickleback, or Pricklebacks, that “the bite of these little furies is so severe, that I have frequently known it, when inflicted on the tail, produce mortification and con- sequently death. They also use their lateral spines (ventral fins) with most fatal effect, that, incredible as it may appear, I have seen one during a battle absolutely rip his opponent quite open, so that he sank to the bottom and died.”’
Jesse mentions a gentleman walking by the side of the river Wey who observed a large Pike in shallow water. Pulling off * Darwin, ‘ Voyage of Beagle,’ iii. p. 13.
+ Whitmee, Proc. Zool. Soc. 1878, p. 135.
46 MR. F. DAY ON THE
his coat and tucking up his shirt-sleeves, he entered the water and tried to intercept the fish’s return to the river, endeavouring to get his hands beneath it and throw it on to the bank. The Pike finding his escape likely to be cut off, assumed the offensive, seizing one of the gentleman’s arms with bis teeth and severely lacerating it: it had evidently argued that it must by force put the cause of its impediment to rout. Mr. J. Faraday, at the Man- chester Anglers’ Association, read a paper, in December 1878, re- cording an instance of apparent intelligence in a Skate which he observed while officiating as Curator of the Aquarium. A morsel of food thrown into the tank fell directly in an angle formed by the glass front and the bottom. The Skate, a large example, made several vain attempts to seize the food, owing to its mouth being on the underside of its head and the food being close to the glass. He lay quite still for a while as though thinking, then suddenly raised himself into a slanting posture, the head inclined upwards and the under surface of the body towards the food, when he waved his broad expanse of fins, thus creating an upward current or wave in the water, which lifted the food from its position and carried it straight to his mouth*.
Certain fishes likewise are endowed with specific means of showing their being affected by anger or terror, as the Electric Hel (Gymnotus electricans), which possesses electric organs of such power as to be capable of causing death even to large ani- mals. Humboldt and others have recorded how the Indians in South America, when they desire to capture these fish, drive horses and mules into waters which they inhabit, when, as soon as dis- turbed, these eels attack the mtruders. They first glide under the horses’ bellies and prostrate them by repeated electric shocks, which, however, by degrees become of less and less intensity, as long rest and nourishment are required to repair the galvanic force which they have expended. It has been considered that the possession of this power is for the purpose of protecting the Electric Hel against Alligators; and it is certainly employed against other fish which it requires as food; but its onslaught on intruding horses must clearly be the effect of anger or terror. The power decreases, and is perhaps eventually lost, in exam- ples which are kept in confinement. Even in British seas, we know, exists a fish endowed with this electric property, viz.
* Nature, Dec. 19, 1878.
INSTINCTS AND EMOTIONS IN FISH. 47
the Electric Ray or Torpedo, commonly known as the Cramp- fish, Zorpedo hebetans and T. marmorata. The instant it is touched it numbs not only the hand and arm, but its effects are said sometimes to extend to the whole of the body. This electric shock is thus described by Kempfer:—The nerves are so affected that the person struck imagines all the bones of his body, and particularly those of the limb that received the blow, are driven out of joint. It is accompanied with a universal terror, a sick- ness of the stomach, a general convulsion, and a total suspension ofthe mind. Asexamples of the Surmullet and Plaice have been found inside Torpedos, while it is manifestly impossible they could have captured such by outswimming them, it has been con- jectured that they must have taken their prey by means of stupefy- ing them with electric shocks. Whether we are to consider attacks made by Sword-fishes upon passing vessels as due to anger at being disturbed, or under the impression that they are attacking their enemies the Whales, is questionable; but it is a well-ascertained fact that the planks of numerous ships, especially in the Indian seas, have been pierced by the strong rostral appa- ratus with which these fishes are provided either for offence or defence.
Fear is frequently shown ; as small birds mob those of prey, so little fish will mob others that they dread. Some small species were kept by Mr. Whitmee in an aquarium with an Antennarius, and were evidently in great dread of their carnivorous neighbour, which they continually tried to torment. In attacking it they always took care to strike at its posterior part, although this was protected by a rock of coral *.
Likewise fish, when hooked or netted, sometimes empty their stomachs by an instinctive act of fear, or to facilitate escape by lightening their load}. Hooker remarks respecting. Gulls, Terns, Wild Geese, and Pelicans in the Ganges valley, that these birds congregate by the sides of pools and beat the water with violence so as to scare the fish, which then become an easy prey, a fact which was, I believe, indicated by Pallas during his residence on the banks of the Caspian Seat. Along the muddy shores of tropical countries and up the sides of large
* Proce. Zool. Soc. 1878, p. 133. + Owen, ‘Comp. Anat.’ p. 419. t ‘Himalayan Journal, i. p. 80.
48 MR. F. DAY ON THE
rivers are many forms of fish, especially belonging to the family of Gobies or Blennies, that wander over the mud or climb rocks left uncovered by the water, or on to the damp stems of trees left exposed by an ebbing tide; and here they craw] about searching for insects: but let them be alarmed, and what an instant com- motion ensues; some dive down at once into the soft mud, others fiy over the water to a place of safety hike a piece of slate sent skimming by a school-boy. Many small fishes, as Blennies &c., when the tide ebbs, are left in small pools, where they conceal themselves under stones. The larger Blennies quit the water, — and using their pectoral fins as organs of prehension and locomotion, creep into suitable holes, where, with their heads towards the sea, they await the flow of the tide, which they know will restore them again to their native element. Often does the observer in the tropics see fish jumping out of the water in terror from some unseen foe ; and should a net be skilfully placed, the cause of this commotion may be taken. I have found the Gar- fish (Belone) is occasionally the form which the smaller herrings are flying from or else the Bonito. The Skipper (Belone vul- garis) of the British seas is observed at times to show great terror at being pursued by Porpoises, Tunies, and Bonitos. Multitudes, observes Couch, then mount to the surface and crowd on each other as they press forwards. When still more closely pursued, they singly spring to the height of several feet, leap over each other in singular confusion, and again sink beneath. The Flying-fish (Hxocetus) is likewise a form which springs out of the water to escape its rapacious pursuers. Friar Odoric, who visited Ceylon about 4.p. 1820, observe that there are “fishes in those seas that come swimming towards the said country in such abundance, that for a great distance into the sea nothing can be seen but the backs of fishes, which, casting themselves on the shore, do suffer men for the space of three daies to come and to take as many of them away as they please; and then they return again to the ocean.” *
Among the coral reefs of the Andaman Islands I found the hittle Heliastes leprdurus abundant. As soon as any thing splashed into the water, they appeared to retire for safety to the branch- ing coral, a locality where no large fish could intrude ; so fright- ened did they become, that on an Andamanese diving from the
* Hakluyt, ii. p. 37.
.
INSTINCTS AND EMOTIONS IN FISH. 49
side ofa boat, they at once took refuge in the coral, remaining in it even after it was removed from the sea. In Burmese rivers, where weirs are not permitted to entirely span rivers (as such would impede navigation), the open side as far as the bank is studded with reeds ; these, as the water passes over them, vibrate, thus occasioning an unusual sound, alarming the fish and fright- ening them over to the weired side of the stream. Every angler knows the natural timidity of fish; and keepers are aware how easily poachers deter Salmon from ascending fish-passes.
At the Andaman Islands fish are captured by the convicts by means of weirs fixed across the openings of creeks. After exist- ing a week or so, it is observed that captures invariably cease ; and it is believed that such is due to barnacles &c. clustering on to the wood of which they are composed. It does not seem impro- bable that the fish have learned to avoid a locality out of terror at those which enter but do not again return.
Many fishes when captured emit sounds which appear to be due to terror, as a Scad or Horse-Mackerel (Caranx hippos), a Globe-fish (Tetrodon), and others grunt like a Pig. A Siluroid found in the Rio Parana, and called the Armado, is remarkable for a harsh grating noise which it emits when caught by hook and line: this can be distinctly heard while it is still beneath the water*. The Cuckoo-Gurnard (Zriga pini) and the Maigre (Sciena aquila) utter sounds, not only while being removed from the water, but the latter likewise, when swimming in shoals, emits grunting or purring noises that may be heard from a depth of 20 fathomst. Herrings (Clupea harengus), when the net has been drawn over them, have been observed to dothe same. The fresh- water Bullhead (Cottus gobio) emits similar sounds.
Speaking of the river on which Brunei is situated in the king- dom of Borneo proper, St. John remarks :—“ I have described in a previous chapter the appearance of the river; but I have not men- tioned that here I have most often heard the Singing or Hum- ming-fish, which sticks to the bottom of the boat, and produces a sound somewhat like that of a Jew’s harp struck slowly, though sometimes it increases in loudness, so as to resemble the full sound or tones of an organ. My men have pointed me outa fish about 4 inches long as the author of the music. It is marked
* Darwin, ‘ Nat. Journal,’ vol. vii. + Yarrell, ‘ Brit. Fish.’ 2nd edit. i. pp. 44, 106.
50 MR. F. DAY ON THE
with alternate stripes of black and yellow across tke back’’*. Pallegroix observes that in Siam the Dog’s-tongue isa fish shaped like a Sole: it attaches itself to the bottom of boats and makes a sonorous neise, which is more musical when several are stuck to the same boat and act in concert+. While on board the brig ‘Ariel,’ observes Adams, in the ‘ Journal of the Samarang,’ “ then lying off the mouth of the river of Borneo, I had the good fortune to hear that solemn aquatic concert of the far-famed Organ-fish or Drum-fish, a species of Pogonias. These singular fishes produce a loud monotonous singing sound, which rises and falls, and sometimes dies away, or assumes a very low drumming character, and the noise appeared to proceed mysteriously from the bottom of the vessel. This strange submarine chorus of fishes continued to amuse us for about a quarter of an hour, when the music, if so it may be called, suddenly ceased, probably on the dispersion of the band of performers.”’ Sir Emerson Tennant observed that a Siluroid fish (Clarias) found in the lake at Colombo is said by the fishermen to make a grunt under water when disturbed. ZElian tells us that the Shad (Clupea) appears to take pleasure in the sounds of musical instruments; while should it thunder during the period they are ascending rivers, they rapidly return to the sea.
Companionship or friendship (as apart from affection) is shown in fishes, while we sometimes perceive such inspired by motives of gain. Mr. H. Shaw, of Shrewsbury, informs me that a gentle- man near that town made the acquaintance of a Trout, over a pound weight, then residing in a brook at Borton Cliff, and wag accustomed to constantly supply it with caterpillars which he obtained from the gooseberry- and other bushes and carried in a cabbage-leaf to the stream. He flicked them off into the water with a small stick, as one day he found that having taken a cater- pillar up in his fingers and thrown it to the fish, it apparently seized it, but seemed at once to eject it, and with a whisk of his tail it immediately disappeared. The same result occurred after every repetition of the experiment, although it latterly returned more quickly than at first. The amount of caterpillars it con- sumed was enormous. Friendship here was doubtless due to this supply of food, while taste or smell must have induced fear,
* Life in the Forests of the Far Hast,’ vol. ii. p. 276. + Pallegroix, /. c. p. 93.
INSTINCTS AND EMOTIONS IN FISH. 51
and caused its rapid flight. Many species are gregarious, moving about in large schools; others, again, merely in pairs.
During the breeding-season most, if not all, Teleostean fishes have more resplendent tints than at any other period of the year, and which may be for the purpose of mutual attraction. A good example is seen in the Salmon, while I have observed the same circumstance occur in the beautiful little Goby (Periophthalmus Schlosseri) which frequents the river Irrawaddi and its banks. Jordan and Copeland*, observing upon the John Darters (£theo- stoma blennoides), remark upon a male in their aquarium which underwent, almost in an instant, an entire change of pattern (in the colours of his body) upon the introduction of a female fish of the same species. Hvyen after two weeks the novelty had not worn off, though his body-colours varied much from hour to hour, but had not reverted to his original dress.
There is a curious instinct of some fishes to take up their resi- dence inside other animals, or else to attach themselves to them in order to profit by the greater power of locomotion in their host, from whose body, however, they draw no sustenance, but merely partake of such food as comes within their reach. These latter, termed Commensalst by Van Beneden, may be either free or fixed to their host ; and a common example of a Commensal is the Sucking-fish (Heheneis), which, having but weak fins, attaches itself to any large swimming or floating object, animate or inani- mate, as ships, sharks, whales, &c., not for the purpose of feeding upon them, but to enable it to profit by their powers of locomo- tion, and so enable it to capture other small fishes, upon which it mostly subsists. Commerson assures us that, having applied his thumb to the adhesive organ of a living Sucking-fish, the adhesion was so strong that it became numbed, and an almost partial para- lysis continued for some considerable time subsequently. During stormy weather it adheres like limpets to a rock. Another cir- cumstance related by Commerson is, that in the Indian seas a ring is fastened round the tail of one of these fish so as to prevent its escape; to the ring is attached a long cord, and it is thus carried in a vessel of salt water; and when boatmen observe a turtle asleep on the surface of the water, they approach as close as they can, then throw the Sucking-fish into the sea: it attaches itself to the breast of the turtle, and is thus drawn into the boat. The
* American Journal, 1878, p. 338. t Bulletin Ac. Belg. 1869, xxvii. p. 621.
52 MR. F. DAY ON TIE
Lump-sucker (Cyclopterus) is said to fix itself by its ventral sucker to the neck of the savage Wolf-fish (Anarrhichas lupus), and adheres thus immovably, tormenting it in such a manner as to cause its death *.
When investigating the fishes at the Andaman Islands in 1870, one of the aborigines brought an example of the pretty yellow-and-white banded Amphiprion percula; and on being told that it was good, observed that she could get numbers more. She took us to an Actinia, which she detached from the coral rock by inserting her hand behind the attachment of this polype; and on shaking it, two more of these little fish fell out. Subsequently this was repeated to twelve others, and all had two living fishes inside them except one, which had three. They asserted that this was their usual abode. A few days previously Captain Hamilton had observed to me that some little striped fishes lived inside a polype at North Bay. One day he dug one out, dragged it to the shore, and captured three little fish from its interior ; replacing them in the sea, they appeared not to know what to do, swimming round and round as if searching for something. The living polype was now returned to the sea, and they at once swam to it, following it as it was dragged back again through the water to its original locality. As Iwas going over to North Bay fishing, he came with me to see if he could not find a specimen. Unfor- tunately, after discovering one and obtaining a fish from it (Am- phiprion bifasciatum), he was stung by the polype, which I did not seef. Dr. Andrews{ has observed upon the Holothuria, or Trepang of the seas of China, that fish live inside it; in fact he saw instances of living fish entering the Trepang. On the Coromandel coast of India at Gopaulpore I found the smail perciform Therapons residing inside Meduse, and which the fisher- mep asserted to be of common occurrence. Gill observes § :—- “In the eastern waters of the United States, however, so far as I am aware, the Stromatoid fish Poronotus similis (Stromateus similis of some authors) seems to be the most common, if not the only associate of several Acalephs, viz. Dactylometra quinquecirra, Zygodactylon groenlandica, aud Oyarea arctica. Under the um- brellas of these species small Poronoti are to be found in the late
* Shaw, Zool. iv. p. 96.
Tt Day, ‘“‘ Obs. on the Andamanese,” Proc. As. Soc. Beng. 1870, p. 176.
{ Meeting Brit. Assoc., Aug. 17th, 1878.
§ Nature, Aug. 30th, 1877, p. 362.
INSTINCTS AND EMOTIONS IN FISH. 58
summers swimming, sometimes even to the number of twenty or more, but generally much fewer.”
It can scarcely be denied that some fishes are endowed with a certain amount of intelligence: thus flat fishes, Pleuronectide, conceal themselves beneath the sand, as, owing to their shape, but little is required to cover them ; consequently by setting up an undulating body movement, this is easily effected. Skates and Rays similarly conceal themselves in the sand. The Sand-Launce (Ammodytes lanceolatus and A.tobianus),commonly frequenting our coasts, lies imbedded in the sand, in which it conceals itself at the depth of about afoot, with its body rolled into a spiral form*. The Stargazer (Uranoscopus scaber) chiefly frequents shallows, where it remains hidden in the mud with merely its head exposed. In this situation it waves the beards of its lips, and especially the long cirrus of its mouth, in various directions, thus allowing the smaller fishes and marine insects which may happen to be swim- ming near, and which mistake these organs for worms, to become instantly seized by their concealed enemy. I obtained in March 1868 at Madras a living example of a fish belonging to this family (Ichthyscopus inermis), the Tamil name of which signified “a diver into the mud.’ It was placed in an aquarium which possessed a bed of mud, into which it rapidly worked itself, first depressing one side and then the other, until merely the top of its head and snout remained above the mud, while a constant current of water was kept up through its gills. While in the mud it resembled a frog ; if lifted out of the aquarium, it ejected water from its mouth to some distance, making a curious noise, half croaking and half snappmgyt. An Indian freshwater Siluroid (Chaca lophioides) conceals itself among the mud, from which, by its lurid appearance and a number of loose filamentous substances on its skin, it is scarcely distinguishable; and with its immense open mouth it is ready to seize any small prey that is passing along ¢. The Angler, or Fishing-Frog (Lophius piscatorius), crouch- ing close to the ground, by the action of its ventral and pectoral fins stirs up the sand and mud; hidden by the obscurity thus produced, it elevates its appendages (situated on the upper sur- face of its head), moves them in various directions by way of attraction as a bait, and the small fishes approaching either to
* Shaw, Zool. iv. p. 81. t Day, ‘ Fishes of India,’ p. 261. + Ham. Buch. ‘Fish. Ganges.’
oA MR. F. DAY ON THE
examine or seize them, immediately become the prey of the fishes (Yarrell). The Weaver (Lrachinus vipera) buries itself in the sands, leaving only its nose out, and if trod on immediately strikes with great force; and we have seen them direct their blows with as much judgment as fighting-cocks*. The Conger- Kel (Conger vulgaris), remarks Couch, is able to insinuate the point of its tail through a crevice and so dilate it as to obtain a passage for its body by a retrograde action; or if that cannot be accomplished, it will examine by its powers of sensation, draw itself along, and, using the tail as a fixed point, elevate its body as a lever and lift itself over any opposing obstacle of considerable height; so that neither the Hel (Anguilla) nor the Conger can be confined within a limited space when their inclinations prompt them to wander from it.
The Jaculator-fish (Chelmon rostratus) frequents shores and sides of rivers near the sea in Asia in search of food. When it sees a fly sitting on the plants that grow in shallow water, it swims to the distance of 4, 5, or 6 feet, and then, with surprising dexterity, it ejects out of its long and tubular mouth a single drop of water, which never fails striking the fly into the sea, when it becomes its prey. This aroused Governor Hommel’s curiosity, and he had a large tub filled with sea-water, in which he placed some of these fish. When they were reconciled to their situation, a slender stick with a fly pinned on its end was placed in such a direction on the side of the vessel that the fish could strike it. It was with inexpressible delight that he daily saw these fish exer- cising their skill in shooting ata fly ; and they never missed their mark. Pallas continued this account from Governor Hommel’s letters two years subsequently, remarking that when the Jacu- lator-fish intends to catch a fly or any other insect which is seen at a distance, it approaches very slowly and cautiously, and comes as much as possible perpendicularly under the object ; then the body being put in an oblique situation, and the mouth and eyes: being near the surface of the water, the Jaculator stays a moment quite immovable, having its eyes fixed directly on the insect, and then begins to shoot without ever showing its mouth above the surface of the water, out of which the single drop shot at the object seems to rise. With the closest attention, Governor Hommel never could see any part of the mouth out of the water, though
* Pennant’s ‘ Brit. Zool.’ iii. p. 170.
INSTINCTS AND EMOTIONS IN FISH. 55d
he has very often seen the Jaculator-fish shoot a great many drops one after another without leaving its place and fixed situation *.
The Common Eel, it is affirmed, voluntarily leaves the water at certain periods and wanders about meadows and moist grounds in quest of particular food, as snails &c.; it is also said to be fond of new-sown peas, which it has been observed to root out of the ground and devour during the night. Ifwe may credit Albertus Magnus, it bas been known during very severe frosts to take refuge in adjoining hay-ricks.
Captain Arn, in a voyage to Hemel in the Baltic, gives the following interesting narrative :—“ One morning during a calm, when near the Hebrides, all hands were called up at 2 a.m. to witness a battle between several of the fish called Threshers or Fox-Sharks (Alopecias vulpes) and some Sword-fish on one side, and an enormous Whale on the other. It was in the middle of the summer; and the weather being clear and the fish close to the vessel, we had a fine opportunity of witnessing the contest. As soon as the Whale’s back appeared above the water, the Threshers springing several yards into the air, descended with great violence upon the object of their rancour, and inflicted upon him the most severe slaps with their long tails, the sounds of which resembled the reports of muskets fired at a distance. The Sword-fish in their turn attacked the distressed Whale, stabbing from below: and thus beset on all sides and wounded, when the poor creature appeared, the water around him was dyed with blood. In this manner they continued tormenting and wounding him for many hours, until we lost sight of him; and I have no doubt they in the end completed his destruction.”
The master of a fishing-boat{ has recently observed that the Thresher-Shark serves out the Whales, the sea sometimes being all blood. One Whale, attacked by these fish, once took refuge under his vessel, where it lay an hour and a half without moving afin. He also remarked having seen the Threshers jump out of the water as high as the mast-head and down upon the Whale, while the Sword-fish was wounding him from beneath, the two sorts of fish evidently acting in concert.
The Thresher or Fox-tailed Shark attacks its enemies or defends
* “On the Jaculator-Fish by Schlosser,” Phil. Trans. Roy. Soc. Lond. 1764, vol. liv. + Shaw, Zool. iv. p. 17. t ‘Land and Water,’ 1879.
56 MR. F. DAY ON THE
itself by blows from its elongated tail; and Couch remarks that it is not uncommon for one to approach a herd of Dolphins (Del- phinus) that may be sporting in unsuspicious security, and by one splash of its tail on the water put them all to flight like so many hares before a hound.
The Pilot-fish (Naucrates ductor) appears to be a very compa- niable disposition, even though we omit the older legends that recorded how they pointed out the course of doubtful navigators, accompanying their ships throughout their voyages, and leaving them only when they had arrived at their desired haven. It is well known that they attach themselves to certain vessels for weeks and even months together, perhaps to obtain the food daily thrown overboard: but why they should accompany Sharks is a doubtful question. Some assert that this large and predacious fish is con- ducted to its prey by these fishes ; others that they eat what the Shark leaves: however this may be, that they are oftenin company is anevident fact. Captain Richards, R.N., during his last station in the Mediterranean, saw on a fine day a Blue Shark, which fol- lowed the ship, attracted perhaps by a corpse which had been com- mitted tothe waves. After some time ashark-hook baited with pork was flung out. The Shark, attended by four Pilot-fish, repeatedly approached the bait; and every time that he did so, one of the Pilot-fishes preceding him was distinctly seen from the taffrail of the ship to run his nose against the side of the Shark’s head to turn it away. After some further delay, the fish swam off in the wake of the vessel, his dorsal fin being long distinctly visible above the water. When he had gone, however, a considerable distance, he suddenly turned round, darted after the vessel, and before the Pilot-fish could overtake him and interfere, snapped at the bait, / and was taken. In hoisting him up, one of the Pilots was ob- served to cling to his side until he was fairly above water, when it fell off. All the Pilot-fishes then swam about awhile, as if in search of their friend, with every apparent mark of anxiety and distress, and afterwards darted suddenly down into the depths of the sea*. Col. Smith states that he witnessed a precisely similar circumstance. M. Geoffrey, on the other hand, mentions how a Piiot-fish took great pains to bring a Shark to a bait.
Two Pilot-fishes accompanied a ship in 1831. from Alexandria to Plymouth. After she came to an anchor in Catwater, their
* Griffith, Cuy. An. King. x. p. 636.
INSTINCTS AND EMOTIONS IN FISH. 57
attachment appeared to have increased; they kept constant guard at the vessel, and made themselves so familiar, that one of them was actually captured by a gentleman in a boat alongside, but by a strong effort it escaped from his grasp and regained the water. After this the two fish separated; but they were both taken the same evening, and, when dressed next day, were found to be excellent eating *.
Contempt does not seem to be unknown in this class of ani- mals, and which appears to be sometimes shown by a stroke of the tail. Anglers frequently observe a fish swim up to their bait, not only refuse it, but give it a lash with their tail, and de- cline to have any thing more to do with it. This may, however, be a symptom of curiosity, which is largely developed in the finny ‘tribes.
The poet Cowper crossing a brook, “ saw from the foot-bridge something at the bottom of the water which had the appearance of a flower.”” ‘‘ Observing it attentively,” he continues, “ I found that it consisted of a circular assemblage of Minnows: their heads all met in a centre, and their tails diverging at equal dis- tances, and being elevated above their heads, gave them the ap- pearance of a flower half-blown. One was longer than the rest ; and often as a straggler came in sight, he quitted his place to pursue him; and having driven him away, he returned to it again, no other Minnow offering to take it in his absence. This I saw him do several times. The object that attracted them all wasa dead Minnow which they seemed to be devouring”’ f.
I would submit that the foregoing facts respecting fish, collected from the writings of naturalists made in various parts of the globe, or else the result of personal observation, must lead us to doubt the very low estimate of the instincts and emotional sensations of the piscine tribes which has been attributed to them by some authors. At the same time we can hardly anticipate that these, the lowest forms of vertebrate life, have their faculties so acutely developed as they are in the higher races. Still it appears we are jus- tified in claiming for some at least of this class of animals that they have attachments, whether in the form of conjugal feelings, paternal and maternal affections, or even of platonic friend- ship. Some construct nests, which they defend, as well as the young when hatched out. The males may act the part
* Yarrell, ‘Brit. Fish.’ 2nd. edit. vol. i. p. 172. + Mag. Nat. Hist. v. p. 290. LINN. JOURN.— ZOOLOGY, VOL, XV. 5
58 MR. A. GC. HADDON ON EXTINCT LAND-TORTOISES.
of nurses to the eggs, either carrying them about in purses on even in their mouths. Lastly, I would allude to the fact that members of two distinct families may combine together for the purpose of attacking another inhabitant of the deep, and thus obtain a supply of food.
On the Extinct Land-Tortoises of Mauritius and Rodriguez. By Atrrep C. Happon, B.A., Scholar of Christ’s College, and Curator in the Museum of Zoology and Comparative Anatomy of the University of Cambridge. (Communicated by Prof. A. Newton, F.R.S.)
[ Abstract, read November 20, 1879. |
Turovaes the generosity of Mr. Edward Newton, C.M.G., F.1L.S., Lieutenant-Governor of Jamaica (late of Mauritius), a fresh collection of the remains of the Mascarene extinct gigantic land-tortoises has been added to his former gift to the Zoological Museum of the University of Cambridge.
- An examination of these bones corroborates the two Mauritian species, Zestudo triserrata and T. inepta, described by Dr. Giin- ther*, but adds no fresh example to that apparently unsatisfac- tory species, 7. leptocnemis. Although possessing a large series of remains from the island of Rodriguez, I am unable, like Dr. Ginther, to distinguish more than the one species, 7. vosmert.
As examples of the inherent tendency to variation in these animals, I may draw attention to the ankylosis of the coracoid with the rest of the shoulder-girdle in one example of 7. inepta, a circumstance which is unique ; also to the variations in the cora- coid of 7. triserrata as to form, markings, &c. The free coracoid of T. inepta is also described for the first time.
From the large number of specimens examined, it is now found that the coracoid of 7. vosmeri was very irregular as to the time of its ankylosis with the rest of the shoulder-girdle, and that it was not the “apparently individual aberration ’’ which Dr. Giin- ther supposed.
Measurements are given of all the most interesting bones, in a manner similar to that adopted by Dr. Ginther in his monograph, to facilitate comparison.
* <The Gigantic Land-Tortoises (living and extinct) in the Collection of the
British Museum.’ By Albert C. L. G. Giinther, M.A., M.D., Ph.D., F.R.S. London, 1877.
MR. E. J. MIERS ON GREENLAND CRUSTACEA. 59
In conclusion, I would draw the attention of herpetologists to these collections of Mascarene Tortoise remains now in the Zoolo- gical Museum at Cambridge, since they form the most complete series of specimens of these very interesting extinct reptiles.
On a small Collection of Crustacea made by Epwarpd WuympPer, Exsq., chiefly in the N. Greenland Seas; with an Appendix on additional Species collected by the late British Arctic Expedition. By Epwarp J. Miers, F.LS. &e.
[Read November 20, 1879.]
Tae North-European and Greenland seas have heen so thoroughly explored by British and Scandinavian naturalists, that it was not to be anticipated that the collection of Crustacea made by Mr. Whymper would contain much of novelty or great rarity, more especially as he appears to have had but few opportunities of col- lecting, several, indeed, of the species having been obtained by purchase from Danish sailors and others. A considerable propor- tion of the species were, however, collected by Mr. Whymper at a single locality—Hare Island, north of Disco Island, in about 30 fathoms of water, concerning which I transcribe the following note :—
“‘T oot three hauls of a dredge as the ship was drifting, and got an immense assemblage of beasts and fishes. These were the richest hauls I have ever made with a dredge. I had to throw away the greater part of the hauls, from the impossibility of preserving the specimens. Thousands of Echinoderms and Mollusks came up.”
It is very much to be regretted that the means of presery- ing the whole of the material dredged on this occasion did not exist; for, as it is, out of a total of twenty-seven species re- corded below, no fewer than twelve were obtained at this locality, although unfortunately several of these are represented by but one or two examples in imperfect condition. The remainder of the collection chiefly consists of parasitic Isopoda and Copepoda and a few marine Copepoda obtained by washing from seaweed. The oceanic Copepoda are not included in the present Report, but have been submitted to Mr. Brady for examination.
5
60 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
The occurrence in fine condition of adult specimens of both sexes of the Branchinecta arctica of Verrill, affords me the op- portunity of correcting an error in the figure of that species in my Report on the Crustacea collected by the naturalists of the late Arctic Expedition; and in an Appendix to the pre- sent paper I have added descriptions of two additional species collected in that expedition and not included in the Report.
The geographical range of species is given, except where I had previously noted it in my Report on the Arctic Crustacea; and some additional localities are cited from Prof. Smith’s recently published “ Report on the Crustaceans of the Atlantic Coast of N. America.”
Dercapopa.
HYAS COARCTATUS.
Hyas coarctatus, Leach, Linn. Trans. xi. p. 329 (1815); Mal. Ped. Brit. pl. xxi. B, fig 13, 29; M.-Edw. Hist. Nat. Crust. 1. p. 312 (1834); Bell, Brit. Caust. p.35 (1853); Goés, Gifu. Vet.-Ahk. Férhandl. p. 161 (1863).
Lissa fissirostra, Say, Journ. Ac. Nat. Sci. Phil. i. p. 79 (1817); Gibbes, Proc. Amer. Assoc. p. 171 (1850).
Several specimens are in the collection from North Greenland ; no definite particulars are recorded with respect to their habitat. This is a very widely distributed species, as it is known to oceur on both the eastern and western coasts of the N. Atlantic, and its circumpolar distribution extends eastward to the Sea of Okhotsk, where a variety of this species has been found which has been de- signated “ alutacea”’ by Brandt.
Crancgon (CHERAPHILUS) BOREAS.
Cancer boreas, Phipps, Voy. North Pole, p. 190, pl. xii. fig. 1 (1772).
Cancer homaroides, O. Fabr. Fauna Greenland. p. 241 (1780); Mohr, Isl. Naturh. p. 108. no. 245, pl. v. (1786).
Crangon boreas, Fabr. Ent. Syst. Supp/. p. 410 (1798); M.-Edw. Hist. Nat. Crust. ii. p. 342 (1837); Kréyer, Nat. Tidsskr. iv. p. 218, pl. iv. figs. 1-14 (1842-43).
Cheraphilus boreas, Kinahan, Proc. Royal Irish Acad. viii. p. 68 (1864); Miers, Ann. & Mag. Nat. Hist. (ser. 4), xx. p. 57 (1877).
Hare Island, north of Disco Island (in about 30 fathoms), two males and four females. From Umenak, several specimens (some purchased of a Danish sailor, and said to have been taken from the “stomach of the frog-fish”’). It is widely distributed
MR. HE. J. MIERS ON GREENLAND CRUSTACEA, 61
through the circumpolar seas; and 8. I. Smith records it from several localities on the North-Atlantic American coast.
Mr. Kingsley, who is engaged upon a monograph of the North- American Caridea, and who has recently published, in the ‘ Bul- letin of the Essex Institute,’ vol. x., a most useful critical list of all the North-American species, is of opinion that the genus Cheraphilus as defined by Kinahan cannot be maintained, as “it has not a single character common to all the species to separate it from Crangon, as restricted by him.” Even if this be the case, it does not follow that the name, having been published, should not be used with a slightly modified definition of the genus, more especially as the genus Crangon, even in the sense accepted by Sars, includes species so diverse in the sculpture of the carapace and postabdominal segments. In my Report on the Arctic Crustacea I adopted Kinahan’s term Cheraphilus, as I considered it would be useful to retain it as a separate designation for those species of Crangon which, like C. boreas and C. salebrosus, Owen, are of very large size, with median and lateral series of spines on the cephalothorax, and with all the segments of the postabdomen longitudinally keeled above, in contradistinction to the smaller less robust species (e. g. C. vulgaris, franciscoruwm), in which the cephalothorax and postabdominal segments are nearly smooth. Nevertheless, not being acquainted with all the species, I retain the name here merely as a sectional division of Crangon in the sense indicated above; intermediate forms undoubtedly occur, and there is no modification in the structure of the limbs of the cephalothorax, such as exists, for instance, in the allied genus Sabinea, Owen.
HIPPOLYTE SPINUS.
Cancer spinus, Sowerby, Brit. Miscel. p. 47, pl. xxii. (1806).
Hippolyte Sowerbei, Kroyer, Monogr. Hippolyte’s nord. Arter, p. 90, pl. u. figs. 45-54 (1842).
Hippolyte Sowerbyi, M.-Edw. Hist. Nat. Crust. ii. p. 380 (1837).
Hippolyte spinus, Bell, Brit. Crust. p. 284 (1855) ; Miers, Ann. & Mag. Nat. Hist. (ser. 4), xx. p. 59 (1877).
Two small specimens were dredged off Hare Island in the same rich haul in which so many of the species here noticed were obtained. One is a female with ova. In this specimen the two last teeth of the median dorsal crest are simple. In the other specimen the teeth of the dorsal carina are themselves denticu-
62 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
lated, and the minute denticules interposed between the teeth on the upper margin of the rostrum are far more numerous; there are four small teeth at the distal extremity of the rostrum, and one or two on the inferior margin. Compared with the much larger specimens obtained during the British Arctic Expedition, the denticulations are more numerous and the dorsal carina not so prominent; yet I do not doubt that the species are identical. On account of the variability of the rostral teeth, I am inclined to doubt the distinctness of H. seeurifrons, Norman (H. Liljeborgz, Danielssen and Boeck), from H. spinus. Many species, it has been observed, increase in size as they advance into the colder regions of the extreme north; and at the same time considerable variation may often be noted in the sculpture and armature of the body. In addition to the localities mentioned in my Report on the Crustacea of the Arctic Expedition, I may note that Stimpson and Smith record this species as common on the coasts of Maine and Massachusetts, and also in the Grand Manan.
HIPPOLYTE POLARIS.
Alpheus polaris, Sabine, Append. Parry’s 1st Voy. x. p. 60, pl. i. figs. 5-8 (1821).
Hippolyte polaris, Ross 8 Owen, Append. Ross’s 2nd Voy., Zool., Crust. p- Ixxxv (1835); M.-Edw. Hist. Nat. Crust. ii. p. 376 (1837); Kréyer, Monogr. Hipp. nord. Art. p. 116, pl. ui. figs. 78-81, pl. iv. (1842) ; Miers, Ann. § Mag. Nat. Hist. (ser. 4), xx. p. 61 (1877).
Hippolyte borealis, Owen, Append. Ross’s 2nd Voy., Cr. p. 1xxxiv, pl. B. fig. 3 (1835); Miers, Ann. § Mag. Nat. Hist. (ser. 4), xx. p. 61 (1877), 3.
Several specimens were dredged off Hare Island. The only two perfect specimens have the rostra *—* toothed, and thus agree more nearly with Kroyer’s diagnosis than do the specimens col- lected in the Polar Sea by the late British Arctic Expedition.
Prof. S. I. Smith, in his “ Report on the Crustaceans of the Atlantic Coast,” records the occurrence of this species on the coast of Labrador, Nova Scotia, and Massachusetts.
HIPPOLYTE GR@NLANDICA.
Astacus groeenlandicus, J. C. Fabr. Syst. Ent. p. 416 (1775).
Cancer aculeatus, O. Fabr. Fauna Greenlandica, p. 289 (1780).
Hippolyte aculeata, Owen § Ross, Crust. in Append.. Ross’s 2nd Voy. p- Ixxxin (1835); M.-Edw. Hist. Nat. Crust. ii. p. 380 (1837);
MR. E. J. MIERS ON GREENLAND CRUSTACEA. 63
Kroyer, Monogr. Hippolyte’s nord. Arter, p. 126, pl. iv. figs. 83-98, pl. v. figs. 99-104 (1842).
Hippolyte groenlandica, Miers, Ann. § Mag. Not. Hist. ser. 4, xx. p. 62 (1877), ubi synon.
Two specimens (male and female) were collected at Hare Island ; and another male was purchased at Umenak of a trader. It occurs, according to Prof. Smith, on the Atlantic coast of Northern America. As in the case of the specimens collected by the late British Arctic Expedition, the male now before me is much smaller than the female.
PANDALUS BOREALIS.
Pandalus borealis, Kroyer, Nat. Tidsskr. 2 R. i. p.469 (1844-45); Voy. en Scand. Atlas, Crust. pl. vi. fig. 2; Goes, Aifv. Vet.-Akad. Forhandl. p- 168 (1863).
One. female individual is in the collection, purchased of a trader at Umenak, with Cheraphilus boreas. It is unfortunately muti- lated, the rostrum being broken off at a short distance beyond the eyes; but there can be no doubt of its identity with Kroyer’s species, with the description of which it agrees in all essential characters. This species is found eastward as far as the Sea of Okhotsk, where its occurrence is recorded by Brandt; and its occurrence in Massachusetts Bay and on the coast of Maine and Nova Scotia is recorded by Smith.
ScHIZOPODA.
MYsIs OCULATA.
Cancer oculatus, Fabr. Fauna Grenland. p. 245. no. 222 (1780).
Mysis Fabricii, Leach, Trans. Linn. Soc. xi. p. 350 (1815).
Mysis oculata, Kroyer, Nat. Tidsskr. ii. p. 255 (1838-39), 3 R. 1. pp- 13, 41 (1861); Voy. en Scand. Atlas, Crust. pl. vii. fig. 2; Buch- holz, Zweite deutsche Nordpolarf. p. 284 (1874); Miers, Ann. § Mag. Nat. Hist. (ser. 4) xx. p. 63 (1877).
A single specimen was purchased of a Danish sailor at Umenak. It agrees with Kroyer’s description and figure in all particulars, except that the lateral spinules on each margin of the telson are somewhat less numerous, about twenty-five instead of thirty-two ; but this is probably a character varying with the age of the indi- vidual. Its length (excluding appendages) is about 8 lines.
64 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
CUMACEA.
Diastyuis RaTuKit.
Cuma Rathki, Aréyer, Nat. Tidsskr. ui. p. 513, pls. v. & vi. figs. 17-30 (1840-41), (N.R.) ii. pp. 144, 207, pl. i. figs. 4 & 6 (1846-49); Voy. en Scand. Atlas, Crust. pl. v. figs. 1 a-u.
Diastylis Rathkii, G. O. Sars, Aberrante Krebsdyr. Cumacea, in Christ. Vidensk.-Selsk. Forhandl. p. 160 (1864); Svensk. Vetensk.-Akad. Handl. 11. (No. 6) p. 7, pl. iii. figs. 8, 9 (1873).
A single individual was included among the species dredged off Hare Island in-about 30 fathoms. Its length is about 63 lines. It is found on the Atlantic coast of Northern America and in the seas of South Greenland, Scandinavia, and Britain, but more abundantly in the higher latitudes, and is perhaps the most common of the northern species of this curious group.
Tsopopa.
IpoTEa, sp. yg?
There is in the collection a specimen, apparently referable to this genus, which, on account of its very small size and imperfect condition, cannot be made the type of a detailed specific deserip- tion, yet seems to be quite distinct from all the species known to me. The head is comparatively large, the frontal margin with a very slightly prominent broad median lobe. The eyes (black) are placed in the middle of the lateral margins of the head. The sides of the body are parallel, the segments of equal width, the three last segments haying the postero-lateral angles subacute. There are four perfectly distinct postabdominal segments, the first three very short ; the terminal segment is triangulate in form, with the angles rounded, broadest at base, where it exceeds in breadth the preceding segments, and with the sides convergent to the distal extremity, which is broad and obiusely rounded. The antennules are apparently four-jointed ; the antenne have six joints exposed, the four first thickened, and the two terminal slenderer and more elongated; the terminal ends in a pencil of fine hairs. The legs are imperfect, but are armed with subter- minal as well as a terminal claw. The operculiform caudal ap- pendages are not oblong, but rather oval in shape, narrowing to the distal extremity. Length 13 line.
The only example collected was obtained by washing seaweed taken on the surface of the North mid-Atlantic in lat. 57° 59’ N.,
MR. E. J. MIERS ON GREENLAND CRUSTACEA. 65
long. 19° 1’ W., with a few specimens of larval Cirripedia. On account of its very small size, I doubt if this specimen can be regarded as adult; but should the characters given prove con- stant, it may be designated after its discoverer, I. Whymperi.
In the parallel sides of-the body and the existence of three per- fectly distinct tail-segments besides the terminal segment, it has much affinity with the Idotea parallela, S. Bate & Westwood, ‘ Brit. Sessile-eyed Crust.’ ii. p. 391 (1868); but in that species (not to speak of other differences) the terminal segment bas the sides parallel, und is semicircularly rounded at its distal ex- tremity.
The Idotea rugulosa of Buchholz, ‘ Zweite deutsche Nordpolarf. Crust.’ p. 285, 1874, note, from Spitzbergen, is also a species with subparallel sides, but has the terminal segment emarginate at its distal extremity.
Idotea bicuspida, Owen, ‘ Cr. in Zool. of Capt. Beechey’s Voyage,’ p. 92, pl. xxvii. fig. 6 (1839), is at once distinguished by its more oval form and the emarginate tip of the terminal tail-segment.
AEGA CRENULATA. Higa crenulata, Liitken, Naturhist. Foren. Vidensk. Meddelelser, p. 70, pl. i. figs. 4, 5 (1858).
A specimen of this fine species is in the collection, which was purchased from a sailor at Umenak, who stated it to have been parasitic on a Greenland Shark. A specimen also from Green- land, in the British-Museum collection, presented some years ago by Mr. Whymper, is said to have been parasitic either on the Shark or the Cod.
Its length is no less than 2 inches 53 lines (60 millims.).
Aiea psora, Linn.
Oniscus psora, Linn. Syst. Nat. (ed. xii.) 1. p. 1060 (1766); Pennant, Brit. Zool. iv. pl. xviii. fig. 1 (1777).
figa emarginata, Leach, Linn. Trans. xi. p. 370 (1815); M.-Edw. Hist. Nat. Crust. iii. p. 240 (1840); Crust. in Cuv. R. A. (ed. 3), pl. Ixxvii. fig. 1.
figa psora, Kréyer, Danmarks Fiske, 2nd deel, p. 40 (1843-45) ; Liitken, Naturhist. Foren. Vidensk. Meddelelser, p. 65 (1858); S. Bate § Westwood, Brit. Sessile-eyed Crust. p. 238 (1862).
Four specimens are in the collection, obtained with 4. crenu- lata. The largest measures about 1 inch 73 lines. It is found in the British, Scandinavian, Icelandic, and Greenland seas; and
66 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
there is, according to Messrs. S. Bate and Westwood, a specimen from Nova Scotia in the Hopean Collection at Oxford.
AMPHIPODA.
HYPERIA MEDUSARUM.
Cancer medusarum, Miiller, Zool. Dan. Prodromus, p. 148 (1776).
Cancer (Gammarus) galba, Montagu, Linn. Trans. xi. p. 4, pl. ii. fig. 2 (1815).
Hyperia Latreillei, M.-Edw. Hist. Nat. Crust. iii. p. 76, pl. xxx. fig. 16 (1840).
Hyperia galba, S. Bate, Cat. Amphip. Brit. Mus. p. 292, pl. xlvui. fig. 9 (1862); S. Bate § Westwood, Brit. Sessile-eyed Crust. ii. p. 12 (1868).
Hyperia medusarum, S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 295, pl. xlix. fig. 1 (1862); Boeck, Skandin. og Arktiske Amphip. p.79, pl. i. fig. 1 (J872), ubi synon.
A single adult female individual was obtained from a Danish
trader at Niakornet.
The synonyma of this species, which appears to be as variable as it is common, is given at such length by Boeck (J. ¢.), that it appears unnecessary to reproduce it in full; and I must refer to his work for further information on the subject. It is commonly distributed throughout the N. Atlantic, British, Scandinavian, and Greenland seas.
ANONYX NUGAX.
Cancer nugax, Phipps, Voy. North Pole, Append. p. 192, pl. xii. fig. 2 (1774).
Anonyx lagena, S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 77, pl. xii. fig. 7, 2 (1862); Boeck, Skand. og Arktiske Amphip. p. 152 (1872).
Anonyx nugax, Miers, Ann. & Mag. Nat. Hist. (ser. 4) xx. p. 96 (1877), ubi synon.
This common species is represented in the collection by three individuals collected, with so many other species, with the dredge off Hare Island.
Onzrsimus EpWARDSII.
Anonyx Edwardsii, Kréyer, Nat. Tidsskr, 2R. ii. pp. 1, 41 (1846); Voy. en Scand., Crust. Atlas, pl. xvi. fig. 1.
Onesimus Edwardsii, Boeck, Skand. og Arktiske Amphip. ui. p. 167, pl. vi. fig. 4 (1876) ; Miers, Ann. § Mag. Nat. Hist. (ser. 4) xx. p. 99, pl. iii. fig. 3 (1877).
MR. EH. J. MIERS ON GREENLAND CRUSTACEA. 67
I refer here, with some hesitation, a number of small specimens obtained by the dredge off Hare Island. The colour of the eyes is indistinguishable in all the specimens. The terminal segment appears to vary somewhat as to the degree of its distal emargina- tion. These specimens agree, however, in all respects with those described by me in the Report on the late Arctic Expedition.
LAaPHYSTIUS STURIONIS.
Laphystius sturionis, Kroyer, Nat. Tidsskr. iv. p. 157 (1842); Lillje- borg, Gifv. Vet.-Akad. Forhandl. p. 132 (1855); S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 110 (1862).
Laphystius sturionis, Boeck, Skandin. og Arktiske Amphip. ii. p. 252, pl. xix. fig. 6 (1876); Schiddte, Nat. Tidssk. 3 R. x. p. 237, pl. v. figs. 9-18 (1876).
Darwinia compressa, S. Bate, Brit. Assoc. Rep. p. 58 (1855); Cat. Amphip. Crust. Brit. Mus. p. 108, pl. xvii. fig. 7 (1862); S. Bate & Westwood, Brit. Sessile-eyed Crust. i. p. 184 (1863).
This species was parasitic on a species of Cod caught by line in 100 fathoms in the North Sea in lat. 58° 53’ N., long. 1° 2’ E. Unlike the Cahgus curtus, parasitic on the same animal (which was distributed over the body of the fish), this species was found only behind the pectoral fins at their bases; and was, as Mr. Whymper notes, sluggish in its movements compared with the other. Only a few specimens were preserved, the adults being females. It has been recorded, as Boeck notes, in the seas of Norway, Denmark, and Britain; but its range does not, as far as I am aware, extend northward to the coast of Greenland.
CEDICERUS LYNCEUS.
{Hdicerus lynceus, M. Sars, Forhandl. Vidensk.-Selsk. Christiania, p. 143(1858); S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 372 (1862); Boeck, Skand. og Arktiske Amphip. uu. p. 259, pl. xii. fig. 4 (1876).
Cidicerus arcticus, Danielssen, Nyt Mag. f. Naturvidensk. p. 7 (1857).
(Edicerus propinquus, Goés, Gifv. Vet.-Ak. Férhandl. p. 526, fig. 19 (1865).
Two specimens are in the collection (one in much mutilated condition), obtained in the dredge-haul off Hare Island in 30 fathoms.
They agree with the descriptions of the species in the form of the body and limbs, the absence of the spur-like prolongation of the wrist of the first pair of legs, and all other characteristics.
68 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
The rostrum, which is obtusely rounded at its apex, has at the apex on the lower margin an almost imperceptible point. It is found in the seas of Spitzbergen, Greenland, Iceland, and Norway.
ATYLUS CARINATUS.
Gammarus carinatus, Fabr. Ent. Syst. ii. p. 515 (1793).
Atylus carinatus, Leach, Zool. Miscell. iii. p. 22, pl. lxix. (1815); M.- Edw. Hist. Nat. Crust. iii. p. 68 (1840); S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 134, pl. xxv. figs. 1-3 (1862); Buchholz, Crust. in Zweite deutsche Nordpolarf. p. 357, pl. x. (1874) ; Boeck, Skandina- viske og Arktiske Amphipoder, ii. p. 324 (1876); Miers, Ann. § Mag. Nat. Hist. (ser. 4) xx. p. 100 (1877).
Amphitho earinata, Kréyer, Kongl. Danske Vid. Selsk. Afh. vii. p. 256, pl. ii. fig. 6 (1838); Voy. en Scand., Atlas, Crust. pl. xi. fig. 1; M.- Edw. Hist. Nat. Crust. iii. p. 41 (1840).
A good series of specimens was dredged from a boat at Noursak
at about 20 fathoms.
It is to be noted that these specimens are all of moderate or
even small size, very much smaller than the specimens obtained by the British Arctic Expedition.
GAMMARUS LOCUSTA.
Cancer locusta, Linn. Syst. Nat. (ed. xii.) p. 1055 (1766).
Gammarus locusta, Fabr. Ent. Syst. u. p. 516 (1793); M.-Edw. Hist. Nat. Crust. iui. p. 44 (1840); S. Bate, Cat. Amphip. Crust. Brit. Mus, p. 206, pl. xxxvi. fig. 6 (1862); Boeck, Scand. og Arktiske Amphip. ii. p. 366 (1876); Miers, Ann. & Mag. Nat. Hist. (ser. 4) xx. p- 101 (1877), ubi synon. -
An adult female is in the collection, taken in the rich haul off
Hare Island.
Several specimens were also washed out of seaweed floating on the surface of the sea at the entrance to Davis Straits, lat. 63°27'N., long. 54° 12' W., with specimens of a species of Copepod (Lhales- tris serrulata, Brady).
Mr. Whymper notes that the species in this tube “ lived in fresh water, and were as lively in it as in salt water.”
The specimens taken from the seaweed are probably none of them fully adult, and some are quite young. In these, the eyes are oval, not uniform in shape; the fasciculi of hairs (in the larger specimens) on the dorsal surface of the fourth to the sixth postabdominal segments are long and slender, there are two hairs in the middle and two or three in each lateral fasciculus; the
MR. E. J. MIERS ON GREENLAND CRUSTACEA. 69
accessory flagellum of the antennules isabout 5-jointed, and ter- minates in a slender filament.
AmPELisca EscHRICHTIL.
Ampelisca Eschrichtii, Kroyer, Nat. Tidssk. 1 R. iv. p. 155 (1842) Boeck, Skand. og Arktiske Amphipoder, pt. 2, p. 528, pl. xxxi. fig. 7 (1876); Buchholz, Crust. in Zweite deutsche Nordpolarf. p. 375, pl. xiii. fig. 1 (1874).
Ampelisea ingens, S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 92, pl. xv. fig. 2 (1862).
A mutilated specimenis in the collection, dredged off Hare Island in 80 fathoms, with the greater number of the species collected. Its range extends from the Scandinavian seas, through those of Iceland and Greenland, to the coasts of Labrador and the Grand Manan.
KUSTRUS CUSPIDATUS.
Eusirus cuspidatus, Kroyer, Nat. Tidsskr. 2 R. i. p. 501 (1844-45) ; Voy. en Scand. pl. xix. fig. 2; S. Bate, Cat. Amphip. Crust. Brit. Mus. p. 154, pl. xxviii. figs. 6, 7 (1862); Buchholz, Zweite deutsche Nordpolarf. Crust. p. 313, pl. iii. fig. 2 (1874); Boeck, Skandin. og Arktiske Amphipoder, pt. 2, p. 502 (1876); Miers, Ann. & Mag. Nat. Hist. (ser. 4) xix. p. 137 (1877).
A single individual (female with ova) was dredged off Hare
Island. It has been found in the seas of Scandinavia, Spitzber- gen, and Greenland.
CAPRELLA SEPTENTRIONALIS.
Squilla lobata, O. Fabr. Fauna Grenl. p. 248 (1780), nee Muller. Caprella septentrionalis, Kroyer, Nat. Tidsskr. iv. p. 590, pl. viii. figs. 10-19 (1843); Voy. en Scand. pl. xxv. fig. 2; S. Bate, Cat. Amphip. Crust. B. M. p. 355, pl. lvi. fig. 3 (1862); Boeck, Skan- dinav. og Arktiske Amphip. p. 696 (1876). Caprella cercopoides, White, in Sutherland’s Journ., Crust. p. 207 (1852). 1 A large number of specimens were dredged from a boat at Noursak at about 20 fathoms. It is probably common in the seas of Scandinavia, Spitzbergen, and Greenland.
CYAMUS NODOSUS. Cyamus nodosus, Liitken, ‘Kong. Dansk. Vidensk. Selsk. Skrift. 5 R. x. p. 274, pl. iv. fig. 8 (1873). ‘ A large number of specimens, including males, females, and young, of this parasite of the Narwhal (Monodon monoceros) were
70 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
obtained of a Danish sailor at Umenak, who stated that they were parasitic on the nose around the horn, and that they were found only at Umenak ; but this is certainly erroneous.
CYAMUS MONODONTIS.
Cyamus monodontis, Liitken, J. c. p. 256, pl.i. fig. 2 (1873).
This species, like the C. nodosus, is parasitic on the Narwhal, but only a few specimens obtained with the preceding have been preserved. These are very easily to be distinguished by the © broader, more flattened segments of the body, which are not roughened and longitudinally suleated as in C. nodosus, and the coxee of the joints of the fifth to seventh legs are not armed with a spine as in that species. Some of the examples collected are, more- over, larger than any of C. nodosus obtained by Mr. Whymper.
PHYLLOPODA.
BRANCHINECTA ARCTICA.
Branchipus (Branchinectus) arcticus, Verrill, Amer. Journ. Sci. 5 Arts (ser. 2), xlviii. p. 253 (1869); Miers, Ann. § Mag. Nat. Hist. (ser. 4) xx. p. 105, pl. iv. fig. 1 (1877).
Branchinecta arctica, Packard in Hayden, U. 8S. Geol. § Geogr. Survey, p- 621 (1874); Amer. Naturalist, xi. p. 53 (1877).
A good series of specimens, males and females (several fully grown), were taken by hand by Mr. Whymper in stagnant pools near Godhavn Harbour. They agree very well with Verrill’s original description (which I had not seen when I wrote the Report on the Crustacea of the Arctic Expedition last year); the second joint of the claspers in the male are bluntly pointed at the tip. They are even larger than the specimens collected by Verrill, attaining a length of 23 millims.
The examination of this series has shown that of the few in- dividuals collected at Discovery Bay, none are nearly fully-grown, nor are there any females among them. It is not impossible that they may prove to be a distinct species, as suggested by me in my Report, on account of the straighter claspers (the basal joint of which has fewer teeth, and the second is less slender), the shorter, broader-lanceolate caudal appendages, &c. ; but more and larger specimens are needed for comparison. In the specimen figured by me the male genital appendages are incorrectly drawn. The ovary is very long and narrow, considerably exceeding half
MR. E. J. MIERS ON GREENLAND CRUSTACEA. Msc
the abdomen in length, and so different from that of Branchipus (B. stagnalis) that I cannot doubt of the generic distinctness of Branchinecta. The terminal joint of the claspers in the female is very much abbreviated. The external male genital appendages are slender, and armed with a curved spine-like fleshy process near the base.
CoPEPODA PARASITICA.
Catieuvs curtus, Muller.
Caligus curtus, O. F, Miiller, Entomostr. p. 130, pl. xxi. figs. 1-2, 2 (1785); Kroyer, Nat. Tidsskr. i. p. 619, pl. vi. fig. 2 (1837); Steen- strup & Liitken, Dansk, Vidensk. Selsk. Skr. (5) v. p. 363 (1861); Olsson, Prodr. Copepod. parasitant. Scand., in Acta Universitat. Lund. p: 6 (1868), ubi synon.
Several specimens, including both males and females, were taken
_ from a species of Cod caught by line in 100 fathoms in the North
Sea in lat. 58° 53’ N., long. 1° 2! E., and, unlike the Laphystius
sturionis, occurring on the same fish, this species was distributed
over the whole body of the animal.
DINEMATURA FEROX.
Dinematura ferox, Kroyer, Nat. Tidsskr. ui. p. 40, pl. i. fig. 5 (1838- 39); Steenstrup and Liitken, Dansk. Vidensk. Selsk. Skrift. (ser. 5) v. p. 376, pl. vii. fig. 14 (1861) ; Olsson, Acta Universitat. Lundensis, p- 17 (1868).
Three specimens were obtained in the rich haul off Hare Island, and two were taken from the “Greenland Shark”? at Umenak. Mr. Whymper notes that they are usually, but not always, found attached to the eyes of the fish. The specimens are in fine condition.
LERNZOPODA ELONGATA.
Lernza elongata, Grant in Brewster's Edinb. Journ. of Sct. vii. p. 147, pl. ii. fig. 5 (1827).
Lernzopoda elongata, Nordmann, Mikr. Beitr. p. 99 (1832); Kroyer, Nat. Tidsskr. i. p. 259, pl. u. fig. 12, pl. ii. fig. 3 a-k (1837); M.-Edw. Hist. Nat. Crust. ii. p. 515 (1840); Baird, Brit. Entomostraca, p. 333, pl. xxxv. fig. 5 (1849); Steenstrup 8 Liithken, Vidensk. Selsk. Skrift.| (ser..5) v. p. 422, pl. xv. fig. 37, 5 2, yg. (1861); Olsson, Copepod. Scandinavia, in Acta Universitat. Lund. p. 37 (1868).
Four female specimens in fine condition of this well-known
72 MR. E. J. MIERS ON GREENLAND CRUSTACEA.
species were bought of a Danish sailor at Umenak, who had taken them from the ‘‘eye of the Greenland Shark,” the situation in which they are always parasitic.
A specimen of a second small species of this genus is in the collection, said to have been taken from the gills of a Trout, and closely allied to, if not identical with, L. salmonea or L. Edwardsii ; as, however, it is in imperfect condition, and the bulla terminating the arms is wanting, it cannot be identified with certainty.
APPENDIX.
Notice of two Additional Species collected during the British Arctic Hxpedition in 1875-76.
A box containing Invertebrata collected by naturalists of the late British Arctic Expedition was brought to the British Mu- seum, after the various groups had been distributed to the natu- ralists entrusted with the working out of the collections, and after my report on the Crustacea had been published. It contained several species from Discovery Bay, among them some additional specimens of Munnopsis typica dredged in 30 fathoms, and the following species, which were not represented in the collections previously examined.
NYMPHON ROBUSTUM. Nymphon robustum, Bell, in Belcher, Last of the Arctic Voyages, ii. Crust. p. 409, pl. xxxv. fig. 4 (1855).
A single individual (adult female with ova) was taken at Dis- covery Bay, in 30 fathoms, off specimens of Crinoids, which I do not hesitate to refer to this species. It is of large size (length be- tween legs when fully extended nearly 4 in.). It is distinguished from LV. hirtwm, which occurred abundantly in the same locality, and more particularly from the variety described by me (Ann. Nat. Hist. 1877, xx. p. 109, pl. iv. fig. 3) as obtusidigitum, by the chele, which have the palmar portion very short and globose, and the fingers long, slender, arcuated, and acute at the tips. Moreover, the whole animal is clothed with a pubescence so short as to be scarcely discernible by the naked eye (on which account, I suppose, the legs are described by Bell as “quite naked ’’), while in NV. hirtwm and obtusidigitum the hairs that cover the animal are long. Bell’s examples were obtained in Northumberland Sound, in 33 fathoms.
ON A SYNTHETIC TYPE OF OPHIURID. 73
BALANUS CRENATUS.
Balanus crenatus, Bruguiére, Darwin, Monogr. Cirripedia, Balanide, p. 261, pl. vi. fig. 6 (1854).
I refer here, but with some hesitation, a small specimen col- lected in Discovery Bay at 30 fathoms. The shell is regularly and steeply conical, white, the compartments smooth, without lon- gitudinal carine, except one, rather obscure, on the carinal valve ; the radii are very oblique, the opercular valves much thinner than is usual in B. ecrenatus; the scutum has, however, scarcely any trace of an adductor ridge, and the spur of the tergum is rounded, but rather longer than in Darwin’s figure of that of B. crenatus, and placed at rather less than its own width from the horizontal angle. The walls of the shell are internally ribbed. Specimens of B. porcatus were collected at the same locality in 20 fathoms.
On a Synthetic Type of Ophiurid from the North Atlantic. By Prof. P. Martin Duneay, F.R.S., F.LS., &e.
[Read December 4, 1879.]
(Puate ITI.)
THERE is a very remarkable Ophiuran which forms part of @ col- lection obtained by Dr. Wallich, during his voyage in H.M.S. ‘Bulldog’ in the year 1860, off the coast of East Greenland. The Ophiuran was presented by him to the Royal Microscopical Society, and I have been permitted to examine and describe it. At first sight, the little form might be considered to be an Am- phiuran of the Hemipholis group, but a glimpse at the upper part of the disk and at the sides of the arms discovers a spinulose con- dition of the upper surface of the first and a hooked arrangement of the latter structures. Theresemblance to species of Ophiothria then becomes more or less striking; but the large scaling of the disk, the absence of the tooth-papille, and the presence of accessory pieces around the aboral edge of the upper arm-plates are dis- tinetive characters, which are, to a certain extent, suggestive of Ophiolepian and Ophiopholian affinities. Nevertheless the dental apparatus does not resemble that of these last genera. There is much in the form under consideration which recalls the shape and spinulation of Ophionyx, M. & T.; but the absence of tooth-papille and the presence of accessory plates to, and LINN. JOURN.—ZOOLOGY, VOL. Xv. 6
74 ‘PROF. P. M. DUNCAN ON A
gpinules on, the upper arm-plates removes the form from that doubtful genus.
Description—The length of the specimen is ;°5 inch, and the body is +4; inch in diameter.
The disk is circular in outline, is swollen inferiorly in the inter- brachial spaces, and is slightly tumid on the upper surface.
The radial shields are small, longer than broad, broadest aborally, and they are separated orally by one or two plates: A central rosette of six subequal plates has the central one pentagonal in shape, the others being more or less rounded. Around the rosette is a row of alternately large and small plates; the smaller fit in between the radial shields, and the others cover much of the interradial spaces, there being only another row reaching to the margin of the disk. A microscopic, transparent, cellular scaling covers the plates of the disk and the spaces between them. There are no long spines to the disk nor accessory scales ; but the radial shields are covered with short, broad-based, bulging, conical spinules, terminating in three small glassy thorns. Similar spinules exist on the edges of all the plates of the rosette, and rarely on the minutely scaled derm between them, and algo, usually, on the plates which separate each radial shield from its fellow. The spinules increase in number towards the margin of the disk and become crowded there.
Beneath the disk and in the interbrachial spaces the ee are there abundant, and they are close externally, but rarer near the mouth-shields. A small scaling separates the mouth-shields from the spinulose part, and there are no large plates on the under- part of the disk, which appears to be covered with skin.
The generative slits, two in each space, are large and wide, and reach to the sides of the mouth-shields.
The mouth-shields are small, more or less irregularly lozenge- shaped, broader than long, the aboral edge being broadly curved or produced into a blunt angle, and the oral angle being more acute and less pronounced. The madreporic shield is more rhombic - in shape than the others. The side mouth-shields are small, narrow, slightly enlarged atthe ends, and the oral margin is slightly concave ; they do not quite unite within, and they do not reach far across, below the arm-plate.
The jaws are short and stout, separated slightly, and each angle is widely apart from its neighbours.
There are no true mouth-papille, but a small flat spine with a ragged top is situated on the side mouth-shield close to the
SYNTHETIC TYPE OF OPHIURID, 75
jaw; it projects downwards and outwards, and is in relation to the tentacle-opening. The jaws are swollen just externally to the very distinct jaw-plate. The true teeth are five in number, and the lowest is small and knobbed; it aborts in some angles ; the next is long, broad and concave orally; and the others are shorter, flat, and slightly rounded wherefree. There are no tooth- papille, neither are there mouth-papillz on the sides of the jaws,
The first upper arm-plate is small, broader than long, widest and curved distally, and narrower near the disk ; it has spinules on it resembling those on the disk. The second plate is larger than the first, is about as broad as long, is broadest distally, the edge being curved outwards. The sides slope in towards the short oral edge, and the whole plate is convex from side to side; it has a few spinules on it in someinstances, There are several(five) small accessory plates which are attached to the curved distal edge, and each one carries a spinule. An accessory plate is also on each side of this upper arm-plate near the proximal edge. The third upper arm-plate is longer than broad and is narrowest proxi- mally ; the accessory plates are in contact with its distal edge, and there is a knob on each side near the proximal edge, but it is not thorned. Three accessory plates are found in re- lation to the next plate and to the eighth; they are not fixed on to the edges, for they separate readily. Theside knobs are found on these plates also, and usually there is a thorn on each.
The first lower arm-plate is very small, rounded distally, and is prolonged towards the mouth upwards, and it bounds part of the wide space between the jaw-angles; the second is much larger, and is square with a slight re-entering aboral curve; the outer angles are rounded, and the inner are incurved for the passage of thetentacle and theincoming of theside arm-plate. Thenextplates are longer than broad, are broadest without, have a more or less straight edge distally, and the oral edge is narrow and rounded; far out on the arm they are longer than broad.
The side arm-plates are stout, long, tumid at the sides when seen from above, and the spines project at right angles from them. The plates encroach on the upper arm-plates, but do not meet along the median line. On the lower surface of the arm they form stout processes, which reach nearly, but not quite, to the median line and form much of the surface. They form large flaps on the sides of the arms, and their free and spined distal edge projects outwards beyond the narrow proximal edge of the plate beyond,
6*
76 PROF. P. M. DUNCAN ON A
The arm-spines are usually four in number, and the upper and lower are the smaller, All are rather short, none being longer than a lower arm-plate, and they are cylindro-conical, constricted at the base and bulging above it, and thence tapering to the end, They are serrate and have large terminal, and occasionally lateral, glassy thorns, and they are striated longitudinally. The lowest spine of the third or fourth side arm-plate has a large thorn on one side, and this is larger on the spine of the next plate; still further out this lateral thorn becomes a curved hook; and at the seventh or eighth plate there is a double transparent claw forming part of a hooked spine; these hooks are large and are continued to the end of the arm.
One tentacle-scale is seen on the arm, and it is large, thin, ragged and spinuled at the free edge, and it is longer than broad. There are no tentacle-scales within the angles of the mouth, and the first is thus absent.
This remarkable Ophiuran came up with the sounding-apparatus from off the sea-floor at a depth of 228 fathoms, about 50 miles north and east of Cape Valloe, East Greenland, and about 200 miles from Cape Farewell, date July 19, 1860, North latitude 60° 42', longitude 41° 42’ W. Dr. Wallich informs me that the “cup” came up full of fragments of granite and felspar, to which were adherent small corallines. Some of them were very delicate, and their perfect condition indicated an undisturbed state of the bottom water where they occurred. There was a sudden decrease of depth close to the spot, and the water shallowed 578 fathoms in three miles,
Although a young form, this specimen presents the normal structures of an Ophiuran, and it is in no way deformed or abortive. Theextreme simplicity of the oral apparatus is in itself remarkable: there are true teeth, but the spines on the side mouth- shields are the only mouth-papille, and they are so called because it is the fashion, erroneously, so to call all growths from the sides of the jaw-angles and side mouth-shields. The use of the small spines on the side mouth-shields is that of tentacle-scales, and they can have nothing to do with alimentation. This remark holds good in the majority of instances where the spine arises from the jaw, close to the side mouth-shield and tentacle-opening,
There are no tooth-papille, and the knob-like projection within the jaw-plate beneath the true teeth, so like that of some Amphiu- rans, isnot seen on all the angles. It comes doubtfully, however, within the description of mouth-papille, and appears to be a true
SYNTHETIC TYPE OF OPHIURID. vi
tooth. The regularity of the pentagon surrounding the oral apparatus is very striking,and go is the extreme separation of the jaw-angles, much of which, however, may be due to post mortem contraction. All the plates on the upper surface of the disk have Separate, broad-based, two- or three-thorned, short spinules on their edges and rarely elsewhere, but the spinulation is not dis- tinct between them. The radial shields have the greatest number of spinules on them. All the spines on the side arm-plates pro- ject at right angles to the arm, and the hooks are glassy at their top. The combination of Amphiuran characters and those of Ophiothrix is thus remarkable.
Miiller and Troschel established the genus Ophionyx and gave its diagnosis in their ‘System der Asteriden, 1842. It has the disk furnished with isolated many-thorned spinules, the mouth has only tooth-papille, there are two generative openings in each interbrachial space, and the arm is furnished beneath with echinulate spines and hooks. Ophionywx armata, M. & T., is des lineated by them and O. scutellum, Grube, is noticed. This genus can hardly be separated from Ophiothriv ; and although Ophionya armata is not without the aspects of the form now under con- sideration, the structural distinctions of the absence of tooth- papille and the presence of accessory plates to the upper arm- plates are incompatible with the union of the species under one genus.
The genus Ophiopholis, Mill. & Trosch., has the upper arm- plates surrounded by a rim of minute accessory plates, and the lower spine of the under arm-platesis a hook ; moreover, the disk is more or less covered with grains or little spines*. There are mouth-papille on the sides of the jaw-angles. In Ophio- lepis, Mull. & Trosch., the disk has naked plates or scales, there are small accessory scales on the disk and arms, a row surround- ing the disk-plates ; there are mouth-papille, and the arm-spines are arranged along the outer edge of the side arm-plates, and there are usually two tentacle-scales. It1is evident, as was suggested at the commencement of this communication, that the alliances of the form are more with these last two genera, but still the distinctness is decided. The extreme simplicity of the dental apparatus, there being no tooth- or mouth-papille on the jaw-angles, only a spine on the side mouth-shield or arising from its junction with the jaw, and evidently a tentacle-scale, is remarkable ; the true teeth are well developed. The disk is symmetrically plated, spinules
* See Liitken, Addit, ad hist. Ophbiurid. p. 11, pl. ii. fig. 16a (1861).
78 MR. F. DAY ON THE HEBRIDAL ARGENTINE.
being between and on the plates in small numbers, but no accessory plates exist on it ; beneath, the disk is covered with skin Spinules are found on the upper part of the arm, and the first and second upper arm-plates are spined. The spines of the side arm- plates project, and there are hooks; there is one tentacle-scale. These characters distinguish the form, and necessitate its entry jnto a new genus, Polypholis. The species is Polypholis echinata.
DESCRIPTION OF PLATE III.
Fig. 1. The disk and part of the arms from above, magnified. 2. The disk from below, magnified. 8. The spinules from the disk, magnified. 4, The arin spines and hooks, magnified. 5, a, 6, c. The tentacle-scale, magnified. 6. Diagram of the mouth-shield, side mouth-shield, and angle of jaw. 7. Polypholis echinata, nat. size.
On the Hebridal Argentine. By Franots Day, F.LS. [Read March 4, 1880.] (Pure IY.) ARGENTINA SPHYRENA,
Sphyrena parva, Rondel. i. p. 227, c. fig.; Gesner, pp. 883, 1061.
Argentina, Willughby, p. 229; Ray, p. 108; Artedi, Synon. p. 17, and Genera, p. 8.
Argentina sphyrena, Linn. Syst. Nat. i. p. 518; Gmel. Linn. p. 1894; Risso, Ichth. Nice, p. 836, and Europ. Mérid. iii. p. 462 ; Cuv. Mém. Mus. i. p. 228, pl. x1.; Nilsson, Skand. Fauna, Fisk. p- 476; Ginther, Catal. vi. p. 203 ; Collett, Norges Fiske, p. 171.
Argentina silus, jun., Nilss. Obs. Ichth. 1835, pp. 3-7.
Osmerus hebridicus, Yarrell, Supp. Brit. Fishes, and ed. 2, ii. p. 183; Rudd, Zoologist, 1852, p. 8504; White, Catal. Brit. Fish. p. 79.
Argentina Cuvieri and Yarrelli, Cuv. & Val. xxi. pp. 418, 418.
Argentina hebridica, Nilss. Skand. Faun., Fisk. p. 474; Yarrell, Brit. Fishes (ed. 3), i. p. 800; Gunther, Catal. vi. p. 203.
Hebridal Smelt, Couch, Fishes of the British Isles, iv. p. 297.
Argentina decagon, Clarke, Trans. & Proc. New Zealand Insti- tute, 1878, xi. p. 296, pl. xiv. f. 2.
Stromsild, Christiania.
BvD 1G Pa V1, Ale @)) Cp hes Ltr. Cee. pylor. 5.
a?
MR. F. DAY ON THE HEBRIDAL ARGENTINE. 79
Length of head 42, of caudal fin 73, height of body 6} in the total length. Hyes with moderately wide adipose lids, the ante- rior of which rather overlaps the posterior above the centre of the upper edge of the orbit; diameter of eye 34 in the length of the head, 1 diameter from the end of the snout and also apart. The shape of the fish is as follows :—The back, sides, and abdominal surfaces flattened, so as to giveit a general tetragonal form, these various surfaces being divided one from the other by a well- developed ridge. These four flat surfaces are further subdivided by other parallel ridges, one of which is a short distance internal to the upper orbito-caudal ridge; a second a little above the pectoro-caudal ridge. In addition to these four secondary ridges, there exists another short one from the lower edge of the base of the pectoral fin to the ventral. Snout conical and somewhat de- pressed; upper surface of the head flat, its sides compressed. Upper jaw slightly longer than the lower; the maxilla scarcely reaches above two thirds of the distance to beneath the front edge ofthe eye. The suborbital ring of bones, the preopercle, opercle, and upper portion of the subopercle with a rather thick adipose covering. eth: none in the jaws; an arched row of small ones across the head of the vomer, and continued on to the anterior and contiguous portion of the palatines; a single row of eight large and somewhat recurved ones are placed on the upper sur- face of the front portion of the tongue. Gill-rakers rather widely separated, thick, and the longest about one fourth the dia- meter of the orbit in length. Mins—First dorsal as high ante- riorly as the body beneath it, its posterior rays about two fifths the height of its front ones; adipose fin placed above the last anal rays; pectoral if turned forward reaches the middle of the eye ; ventral inserted in the middle of the distance between the end of the snout and the base of the caudal fin, while it is beneath the last dorsal ray ; anal highest anteriorly, where it equals the length of the base of the fin; caudal forked. Scales large, thin, higher than long; those along the back adherent, those on the sides more deciduous. Minute ossicles, having a stellate or spinate form, exist on the scales of the back, and also on some of those in the abdominal region. The row of scales immediately beneath that of the lateral line is the largest ; most have somewhat crenulated edges. Lateral line on a row of smaller scales, well marked, and passing to the centre of the base of the caudal fin. Cccal appen- dages—tfive long ones, loaded with fat. The example is a male, full of milt. Colowrs—of a light olive along the back, becoming silvery
80 MR. F. DAY ON THE HEBRIDAL ARGENTINE.
white on the sides; a black spot at the upper edge of the orbit and a smaller one on the snout a darkish longitudinal mark along either lobe of the caudal fin near its outer edge.
I now propose considering whether Argentina sphyrena, Linn., and A. hebridica, Yarrell, are or are not identical, and which Collett, as I believe, with good reason states they are. Valen- ciennes gives the formula thus :— ;
Argentina sphyrena...... DOF PAL 2 VOLO een Gls [UBUPUWIGD 5m oce20000000- DR ilee VAR STOPS Ve lel yeaa
But these numbers evidently are subject to great variation ; and no undoubted criterion can be deduced from the number of fin-rays or scales. Nilsson found from 14 to 20 cecal append- ages in A. hebridica, whereas A. sphyrena is said to have only 12. If so great a variation as 6 can occur in one undoubted species (especially as the present example had only 5 long ones), it would be hazardous to consider that these variations in number are suf- ficient to constitute distinct species.
The principal difference pointed out in the British Wineemn catalogue is that in Argentina sphyrena the height of the body is 8 in the total length, while in A. hebridica it is 54 (this should be 51). The following are the proportions of some I have examined or obtained the accurate dimensions of, as Collett has stated that the proportionate length to height varies with age ; fractions are omitted if very trivial :—
1 from Sicily ...... 5 inches long, height 1 in 8 of totallength. British Museum.
1 ,, Norway ..6 +5 ae le LS i Collett.
ee eB utemn we GP UaM dD Genet eben clu maa 5 Yarrell.
1 , N.Zealand69_,, st herleey: 0 Clarke.
a ee Osi temenntes Ti 5 silane Liussin dey es British Museum. Wg. Nites cscs TB 5 1, tela (GE * British Museum*, 1 ,, Norway ...83 ,, oH ieedbesaeta) oy Collett.
res) NEV C vacua Oe a eas sl GE a Day.
There can be no doubt but that my Skye example agrees with Yarrell’s, wherein he found the height as 1 in 57, but does not dis- tinctly say whether his specimen was a skin or in spirit. Valen- ciennes states his examples of the same species were 1 in 8 of the total length, or similar to what he found existed in A. sphy- vena. As we seein those examples which have been preserved in alcohol, some the height of whose body is 6, others 62,7, or 8, in the total length, it is evident that this proportion varies, and
* ‘Ihe length of the caudal fin is deduced from the average of other speci- mens, as this fin is often broken in museum examples.
MR. F. DAY ON THE HEBRIDAL ARGENTINE. 81
cannot be taken as a means for the discrimination of the two so- called species, which must be considered as one.
There is one subject respecting the air-bladders of the fishes of this genus which is of great interest, belonging, as they do, to the family Salmonide, wherein this organ is of the Physostomous variety, but destitute of any chain of ossicles connecting it with the internal ear, as seen in the true freshwater Cyprinide, Cha- racinide, and Siluride*. Valenciennes mentions that the museum at Paris had received a very good example of Argentina silus, a little more than a foot in length, from the Bergen Museum. He supposed that it had been captured at a great depth, for its sto- mach was inverted. This inversion of the stomach is observed in fishes suddenly brought up from great depths; and is known to be caused by the pressure of the water being rapidly lessened or entirely removed, causing the gases in its interior to expand and either burst the air-bladder or force the stomach into the mouth. I do not think this phenomenon has been observed in Physosto- mous fishes, to which the Salmonide belong, as the pneumatic tube, which is pervious throughout life, acts as a safety-valve, and would permit this rapidly expanding gas to find an exit by the alimentary canal. This brings us to the question of whether the Argentines are or are not Physostomi, the same as the remainder of the Salmonide. Valenciennes states that they belong to the Physoclisti, as, so far as he could ascertain in three well-preserved examples, no pervious pneumatic tube could be detected.
Ifthe Argentines undoubtedly belong to the class of fishes having closed air-bladders, it is an exceedingly interesting fact— one, however, I have as yet had no opportunity of investigating. The genus Salmo contains fish, some of which are anadromous, others freshwater; but their affinities are unmistakably marine. And here we observe another link in finding Atherina, one of the deep-sea Salmonide, possessing a closed air-bladder smaller than perceived in other genera of the same family, perhaps due to the depths at which it resides. For were it large and of the Physo- stomous type, probably it would be unable to keep it distended with gas, as such would be pressed out through its pneumatic tube, unless the same mechanism were adopted as we see in the
* Physostomous fishes are mostly freshwater forms, haying a chain of ossicles as described ; or if marine, they are mostly surface-swimmers or littoral Species, with a tubular prolongation of the air-bladder instead of a chain of ossicles. Physoclistous fishes appear to be, as a rule, marine or of marine origin,
82 MR. F. DAY ON THE HEBRIDAL ARGENTINE.
ground-feeding Loaches and some of the Siluroids, where this organ is protected from pressure by being enclosed in bone by a deve- lopment of the parapophyses of the anterior vertebre.
We find a figure and description of this species in Rondelet’s Marine Fishes, which was reproduced by Gesner. Willughby gives “Pisciculus Rome Argentina dictus. Sphyrena parva sive Sphy. rene secunda species, Rondeletio Gesner 1061,’—very clearly in- dicating that this author referred to the fish described by Ron- delet and Gesner ; while it was likewise his Roman deep-sea fish from whose air-bladder materials were obtained for the manufac- ture of artificial pearls. Ray copies almost verbatim from the authors I have quoted. Doubtless Artedi’s species was identical with Argentina sphyrena of Linneus, but not with Gronovius’s fish. Risso, in his ‘ Ichthyology of Nice,’ refers to the same fish, under Linneus’s name, as being captured throughout the year in the sea, as well as to its air-bladder being employed in artificial pearl- making. The synonyms I have given likewise show how it has been observed upon by Cuvier, Nilsson, Yarrell, Valenciennes, &e., the last-mentioned author, as is well known, having a par- tiality for changing specific names. Thus he gives Argentina sphyrena of Linneus and Cuvier as A. Cuvieri, admitting the two to be identical: and he changes Osmerus hebridicus, Yarrell, into Atherina Yarrelli.
Up to the present time I have only been able to find three British examples of this fish recorded, and all mentioned by Yarrell. Two were from the S.W. coast of Scotland, where the fishermen reported it as well known, but rarely seen: one of these was 83 inches long, taken in 1836, full of roe, in the bay of Rothesay, Isle of Bute; the second, 6} inches in length, in November 1837 near the same spot, on a hand-line baited with a piece of mussel, and in 12 fathoms of water, about 200 yards from the shore. The third, of which I have been unable to obtain any description, came from the German Ocean off Redcar, in York- shire, where it was obtained by Mr. Rudd, who showed it to Mr. Yarrell. -
Couch, when he published his work on the Fishes of the British Isles in 1862, did not appear to have met with the spe- cies, although he observes that it “is not rare in the sea near the islands to the north of Scotland,” but omits giving his authority for the statement. He likewise remarks, “I am informed by Mr. John Iverach of Kirkwall, in Orkney, that it is not known to the fishermen of that island.” Four years subsequently (1866) Dr.
MR. F. DAY ON THE HEBRIDAL ARGENTINE. 83
Giinther, in the ‘ Catalogue of the Fishes of the British Museum,’ vi. p. 203, quotes “ Zhe Argentine, Low, Fauna Orcadensis, p. 225,” as a synonym of Argentina hebridica, which reference, were it cor- rect, would show that both Yarrell, Couch, and other antecedent authors had been in error in believing that this fish had not, pre- viously to the capture of the Bute example in 1836, been recorded from the British seas. On referring, however, to Low, it will be seen that he terms his single example of an Orkney fish (which was not above an inch in length) “the Argentine,” and refers to Pennant, who applied this name of Argentine to the Maurolicus borealis, pertaining to the family of Sternoptychide ; and Low’s references to Willughby, Ray, and Linneus may have been copied from Pennant’s ‘ British Zoology.’ Irrespective of this, in vol. v. p. 389 of the British-Museum catalogue, Low’s single Specimen is also referred to Waurolicus borealis, while it is mani- festly impossible that one fish can pertain to two distinct families.
The example I have to record is one of 9°5 inches in length, in a good state of preservation, having been placed in whiskey imme- diately after it had been captured. It was taken in October 1879, near Lochalsh, off the Skye shore, by a fisherman using a hand- line, the hook being baited with a piece of mussel; its captor con- sidered it very rare, stating that he had only once previously taken an example. Not only is the specimen an interesting one, but likewise the locality from which it was received, the N.W. coast of Scotland, showing that it is by no means improbable that it may exist all round that country.
The Argentine is found extending from the shores of Norway to those of the west coast of Scotland and the German Ocean on the east coast of Yorkshire; thence through the Mediter- ranean to the Balearic Isles and along the southern shores of Europe, being taken, we are informed, all the year round in the sea off Rome; while most authors state it to be a deep-sea fish.
Mr. Clarke has described and figured Argentina decagon from New Zealand, where a unique example was procured, and which does not differ from my specimen, except that it is stated to have four rows of scales between the lateral line and base of the dorsal fin, whereas I only count three. At first sight it would seem strange that this species could stray from the North Atlantic to the South Pacific ocean, even if we accepted Mr. Clarke’s sug- gestion that “ it would be of excessive interest to have more proof than mere imagination that our antipodean species had gradually worked its way ‘sub mari’ in those cold lower strata of water to
84, ON A NEW GENUS OF THE FAMILY LIPARID#.
our coast.” Several European species of fish have been found existing in more or less plenty in that portion of the world and in Tasmania—as Chondropterygian fishes destitute of air-bladders, and Sciena aquila,