| IPE POE DT AIA COLE. to-read Aw tah : NE ee ae TRONS AINE We ae ee ea ; t Ni i iat vi i ‘ | cn } ay sa a q cy aT Ne Piahieye sw } f Alt 4 } W A Haha gn oh te dai! i it nN yuh if py ave Vs a ba Rau ; NN a eG fa hae (ODES) id i ay aes tah sii IAM yi i if hes’ Ay MN hy i + ny - Pat ‘ t ‘ aay a eit Bak a iA ay | Laan ot Bn ear Ags ee THE ANNALS AND MAGAZINE OF NATURAL HISTORY, INCLUDING ZOOLOGY, BOTANY, ann GEOLOGY. Y (BEING A CONTINUATION OF THE ‘ANNALS’ COMBINED WITH LOUDON AND . CHARLESWORTH’S ‘ MAGAZINE OF NATURAL HISTORY.’ ) CONDUCTED BY ALBERT C. L. G. GUNTHER, M.A., M.D., Ph.D., F.R.S., WILLIAM S. DALLAS, F.LS., WILLIAM CARRUTHERS, F.R.S., F.L.S., F.GS., AND WILLIAM FRANCIS, Ph.D., F.L.S. ECan VOL, XII.—FIFTH SERIES, ? Vo 5 etic le, \ AARZI1O a) Lotions Muse yee LONDON: f PRINTED AND PUBLISHED BY TAYLOR AND FRANCIS. 7 SOLD BY LONG GREEN, READER, AND DYER; SIMPKIN, MARSHALL, i AND CO.; KENT AND CO.; WHITTAKER AND CO.; BAILLIERE, PARIS: | MACLACHLAN AND STEWART, EDINBURGH : HODGES, FOSTER, AND CO., DUBLIN: AND ASHER, BERLIN. q 1883. “Omnes res create: sunt divine sapientia et potentix testes, divitia felicitatis human :—ex harum usu Jonitas Creatoris; ex pulchritudine sapientia Domini; ex cconomid in conservatione, proportione, renovatione, potentia majestatis elucet. Earum itaque indagatio ab hominibus sibi relictis semper estimata ; a veré eruditis et sapientibus semper exculta; malé doctis et barbaris semper inimica fuit.”’—Linnavs. ‘Quel que soit le principe de la vie animale, il ne faut qu’ouvrir les yeux pour voir qu’elle est le chef-d’ceuvre de la Toute-puissance, et le but auquel se rappor- tent toutes ses opérations.”—Bruckner, Théorie du Systéme Animal, Leyden, 1767. week we wees Ae mlbersylvanipowers Obey our summons; from their deepest dells The Dryads come, and throw their garlands wild And odorous branches at our feet; the Nymphs That press with nimble step the mountain-thyme And purple heath-flower come not empty-handed, But scatter round ten thousand forms minute Of velvet moss or lichen, torn from rock Or rifted oak or cavern deep: the Naiads too Quit their loved native stream, from whose smooth face They crop the lily, and each sedge and rush That drinks the rippling tide: the frozen poles, Where peril waits the bold adventurer’s tread, The burning sands of Borneo and Cayenne, All, all to us unlock their secret stores And pay their cheerful tribute. J. Taytor, Norwich, 1818. ar RC F CONTENTS OF VOL. XIL. [FIFTH SERIES, ] NUMBER LXVIL. Page 1. Materials towards the History of Anchinia. By A. Kowa.vev- any and J, -Bannotg, + (Plates [—1M1.).. coer et ole oe ee nae 1 Il. On the Mutual Relations of the Bunotherian Mammalia. By pt) MCC Eg eee rah ota Mawes tarde a Kitsap Wiest ¢ ols oe a WS Suitrsaed ne Aisle ate 20 ILI. On the Microscopic Structure of thin Slices of Fossil Calci- epunpico-e by bind. CARTER, WOR 5. SC. 3 ca ee eu csow dace mnaeans 26 IV. On the Presence of Starch-granules in the Ovum of the Marine Sponges, and on the Ovigerous Layer of Suberites domuncula, Nardo. Se Neral AEM Ra GcG i) a. laste a cient eal ataiay a pig shed aye) abe d slvlch 30 V. The Microscopic Sexual Characteristics of the American, Portu- guese, and Common Edible Oyster of Europe compared. By Joun “3. JESSIE GS ORIE WGEInIE Con Gr CIR OD Clog aeitien Sue crccmomaccies cn od VI. Occurrence of Rhinodon typicus, Smith, on the West Coast of Pe erry inept yay ae ATV gy basic an creas) che se) ana ok SL Ro ah » asdf suaiw st om oant 48 VII. On a Third Collection of Lepidoptera made by Mr. H. FE. Hobson in Formosa. By Arruur G. BuruEr, F.L.S., F.Z.8., &e. . 50 VIII. Note on the Detection of Polycystina within the hermeti- cally closed Cavities of certain Nodular Flints. By Surgeon-Major Separate rE Ue Gime ry aR, edt AN aes 5 lee oars lacahenaloises a 3 Ale woleeke 52 IX. Notes on the Structure, Postembryonic Development, and Systematic Position of Scolopendrella. By J. Woop-Mason, Deputy Superintendent, Indian Museum, Calcutta ........... 0... cee eee, 53 Proceedings of the Geological Society.....,.....0.+sceeeecues 63—65 New Book :—The Young Collector's Handbook of Shells. By B. B. KO OD RE Cras OCG. aa eats is as nie s/ahs cn sn Raine aieisanaua as meee 65 1V CONTENTS. Page The “Crag Mollusca,” by Searles V. Wood, F.G.S. ; Mediterranean Mollusca, by J. Gwyn Jeffreys, LL.D., F.R.S.; Further Obser- vations on the Dimorphism of the Foraminifera, by MM. Munier- Chalmas and Schlumberger; On Radial and Bilateral Symmetry in Animals, by H. W. Conn; Observations on Blastogenesis and Alternation of Generations in the Salpe and Pyrosomata, by M. ONCE <5 a 550 ah celeron rte ret one ha pee ea ae eee 66—70 NUMBER LXVIII. X. Further Contribution to the Knowledge of the Family Trntin- nodea.. By Dr. Hermann Fou. (Plate TV:).........-0. + -es sem 75 XI. Descriptions of some new Genera and Species of Curculionidae, _ mostly Asiatic.—Part II. By Francis P. Pascor ..... Oe re. 88 XII. On some Lepidoptera from the Victoria Nyanza. By ARTHUR G. BULLER, FILS. EUZiS, ccs) ae mime eee 101 XIII. Descriptions of two new Species of Milionta, a Genus of the Lepidopterous Family Luschemide. By Artuur G. BuriEr, 104) Ges Pal On Ate Pat aa ee Mineo Pee et tion 107 XIV. On Rudimentary Wings in the Coleoptera. By Dr. H. 1056 6 A ee Sr Mae Rene MME ERAGE. oo « c 108 XV. On the Systematic Relations of the Carnivora Fissipedia. By E. D. Cops XVI. Notes on the Mollusca in the Great International Fisheries Exhibition, London, 1883, with the Description of a new Species of Pleurotoma. By J. Gwyn JEFFreys, LL.D., F.RS. ...........- 116 XVII. On two Freshwater Sponges (Spongilla nitens, Carter, and S. Bohmit, sp. n.) collected by Dr. R. Bohm in the River Ugalla near Lake Tanganyika, By M. EiiremnpoRr | .. 2... 2. <2... eee 120 Proceedings of the Dublin Microscopical Club .............. 123—128 Proceedings of the Geological Society New Books :—Mémoires de ?Académie Impériale des Sciences de St. Pétersbourg. 7° série, tome xxxi. No. 5. Miscellanea Silu- rica IIT. I. Supplement to the Monograph of the Russian Leper- ditia. 1. The Crustacean Fauna of the Furypterus-beds of Rootzikill, Oesel. By Magister Fr. Scumipt, Fellow of the Academy.—Proceedings of the Bristol Naturalist’s Society. New Series, vol. iv. part ii—Journal of the Royal Geological Society of Ireland. Vol. xvi. part ii.; n. s. vol. vi. part ii. for 1881-82.— Transactions of the Geological Society of Glasgow. Vol. vii. part i. for 1880-82 ................ 129—184 A proposed new ‘Nomenclator Paleontologicus ;’ Selenotropism in Plants, by M. C. Musset ; Jumping Seeds and Galls, by Charles V. Riley ; The “Crag Mollusca,” by J. Gwyn Jeffreys, LL.D., F.R.S.; on a new Crinoid from the Southern Seas, by P. Herbert Carpenter, M.A., Assistant Master at’ Eton College. CONTENTS. Vv NUMBER LXIX. Page XVIII. On the Classification of the Orders of Orthoptera and Nearoptera, by AS. PACKARD, JUns, «5.0 04s ste sees a 145 XIX. On Ure’s “ Millepore,” Tabulipora (Cellepora) Uri, Flem. By JOHN VOUNG) EIG.S.-hceceaes sags sed scent eae meeseensen s 154 XX. Descriptions of some new Species of Lepidoptera. By ARTHUR CEE ETT Masi ED Zit CEC. a a wie lu atch a anne cbd aid Ree aucles sage eye aime 158 XXI. Descriptions of some new Species of Reptiles and Batrachians in the British Museum. By G. A. BouLenGER. (Plate V.) .... 161 XXII. On the ‘Classification of the Coleoptera of North America,’ by Dr. J. L. LeConte and Dr. G. H. Horn (Washington: 1883), By MEPL Ve Ae NEAT CEI WS 1e8 sly. 25 A «dud eke Solon didn 167 XXIII. Notes on some Fossil Plants from Northern China. By VSAM EWVRERER M7. datas Woreld yceeoa cur & aliiieartle «abe tcrth «aah 172 XXIV. On the Structure and Affinities of the Genus Tristychius, Agass. By Tuomas Srock, Natural-History Department, Museum of Science and Art, Edinburgh, (Plate, Vals ese wes. teens 177 New Books :—Die Bartenwale der argentinischen Kiisten. By Dr. H. BurmetstEr, Directeur du Musée public de Buenos Aires, &c.—Life of Sir W. E. Logan. By Bernarp J. Har- RINGTON.—A Monograph of North-American Phyllopod Crus- tacea. By A. S. Packarp, Jun.—A Monograph of the Insec- tivora, Systematic and Anatomical. By G. E. Dosson, M.A., FEES SS ey eater rahe srael Soa: aeons tah Laut Soha Saves 190-204 Observations on Actinospherium Eichhorni, by Miss 8. G. Foulke ; The “Crag Mollusca ”—DPurpura tetragona, by 3. V. Wood; A Social Heliozoan, by Prof. Leidy ; On the Genus Hyliota, by G. TGR ISR oes aie te hs RO RRP CT AM et NO 206—210 NUMBER LXX. XXYV. Note on some Earthworms from India. By Frank E. Bepparp, M.A. Oxon., F.R.S.E., Naturalist to the ‘ Challenger ’ TSS CISCO EEL omy Yiee.c aca aes ELE vei tie ie ae ene mie Orde 213 XXVI. Remarks on the Lizards of the Genus Lophognathus. By ee stVUELN GICEMey Steet Slee Ae aac ayer chs are: wae) Sere aes byw w eho hays 225 XXVIII. Neuroptera of the Hawaiian Islands.—Part I. Pseudo- Neuroptera. By Roprert McLacuuan, F.RB.S. &e.. ............ 226 XXVIIL. Contributions to a Knowledge of Malayan Entomology. SEEM ENV IAW\ EGC LEST AND 8 cre ota alelorscete ie ee Wa cle Geen wale Vises 241 vi CONTENTS. Page XXIX. Notesonthe Pale oz0ic Bivalved Entomostraca.—No. XVI. By I. Rurrerr Jonus, F.R.S., F.G.S., &c. (Plates VI. & IX.) .... 243 XXX. On Guard-Polyps and Urticating Cells. By Dr. R. von WEEN NIE ELD: 40 tocsreis “(a4 tate tete ohareiete bere atc teae ai ete loners tote eae 250 XX XT. On a Case of Commensalism of a Caranv anda Crambessa. By Mi AGODERROY LGN Bi ois, siege s, casc/eys e2oga:cee ieee ae te ee ee 264 New Books:—Minute Structure of the Central Nervous System of certain Reptiles and Batrachians of America. Illustrated by ermanent Photomicrographs by Joon J. Mason, M.D.— Temoirs of the Geological Survey of India. Paleeontologia Indica, being Figures and Descriptions of the Organic Remains procured during the progress of the Geological Survey of India. Published by order of his Excellency the Governor-General of Indiain Council. Series x. Indian Tertiary and post-Tertiary Vertebrata. Vol. I]. Part 1. Siwalik Rhinocerotide. Part 2. Supplement to Siwalik and Narbada Proboscidia, with 11 plates: 1881. Part 3. Siwalik and Naybada Kquidee, y with 5 plates: 1882, Part 4. Siwalik Camelopardalidee, with 7 plates : 1883. Part 5. Siwalik Selenodont Suina &c., with 3 plates: 1883. By R, LypEKKER, B.A., F.Z.8., Geological Survey of India... 270—274 Note on the Intelligence of the American Turret-Spider, by Dr. McCook ; Complete Biological Evolution of the Elm-tree Aphis ( Tetraneura ulmi, Aut.), by M. J. Lichtenstein ; Elevated Coral Reefs of, Cuba, by “W/O: Crosby e.g. do -guce cc cdete ce 281—283 NUMBER LXXI. XXXII. Contributions to Micro-Paleontology.—On Stenopora Howsti, Nich., with Notes on Monticulipora? tumzda, Phill., and Remarks on Tabulipora Urvi, Young. By H. ALLEYNE NICHOLSON, M.D., D.Se., Regius Professor of Natural History in the University of Aberdeen. (Plate ee) iin lohsieanecs, sateen Gyalnya alee ero ge tee tere ie as ee 285 XXXII. Neuroptera of the Hawaiian Islands.—Part IL. Plani- pennia, with General Summary. By Ropertr McLacuuay, F.R.S. (CdGhcia bcROCR See Rane ian merino ano oceGc.so000.000.0000 - 298 XXXIV. On the Answerable Divisions of the Brain in Vertebrates and Invertebrates. By Prof. OwrEn, C.B., F.RS., &............:. 308 XXXV. Remarks on the Nyctisaura. By G. A. BoULENGER .. 308 XXXVI. Contributions to our Knowledge of the Spongida. By H. J. Canter, F.R.S. &c. (Plates XI., XI., XJIT., & XIV.) .... 308 XXXVIT. Spicules of Spongilla in the Diluvium of the Altmuhl Valley, Bavaria. By H. J. Carrer, F.R.S. &c. (Plate XIV.) .. 829 XXXAVUI. Descriptions of two new Species of Asterotdea in the Collection of the British Museum, By F, Jerrrey Brun, M.A, ., 333 CONTENTS. vl Page XXXIX. Descriptions of two new Species of the Genus Megalops (Coleoptera, Stenini). By CHartes O, WATERHOUSE .......... 335 XL. On the Morphology of the Myriopoda. By Dr. A. S. Hee mles ROAR DT epad LDN hang hs ahscasala sens at Siek «=. eR GY ike wil ee, ene ache 337 XLI. Contributions to a Knowledge of Malayan Entomology.— Peeeimeleres Es yi Wir Ere A DISTANT a icas't.cln dy oaies saps One ee ces 351 Lueilia macellaria infesting Man, by Frederick Humbert, M.D., ; F.C.S.; Fish Mortality in the Gulf of Mexico, by 8S. T. Waller ; On the Organization of the Crinoidea, by M. E. Perrier. , 353—358 NUMBER LXXII. XLII. Remarks on an Essay by Prof. G. Lindstrém entitled “ Con- tributions to the Actinology of the Atlantic Ocean,” and a Reply to some of his Criticisms. By Prof. P. Martin Duncan, F.R.S., PMOL Se cues ya Gieioin-aferissrs Ss Saree Ue Oe ARON AH, 361 XLIII. Notices of British Fungi. By the Rey. M. J. BerKELEy, BES. alld... By, EXROOMH, Bis. stE WcQies). 5 60559) «33s ofa qcaneywiae iePars « 370 XLIV. Mochlonyx (Tipula) culiciformis, De Geer. By F. MEINERT XLV. Notice of a new Genus and Species of Lucanoid Coleo- ptera. By Cuarvtes O, WATERHOUSE XLVI. Descriptions of new Lepidoptera from the Viti Islands. Bvearraun G, borumn, BUS, BiZ.S., Ges. weve. as eee ip ev ees 389 XLVI. On some new Siliceous Sponges collected by M. Pechuél- Lésche in the Congo. By Dr. Wintiam Marsuatu. (Plate XV.) 391 XLVIII. Additions to the Australian Curculionide.—Part X. By Francis P. Pascor Proceedings of the Geological Society...... 0.0... .0. eee 422, 423 On the Internal Sacculina, a new Stage in the Development of Saecu- lina Carcini, by M. Yves Delage; On the Fossil Flora of Green- land, by Prof. O. Heer; On the Pelagic Fauna of the Swiss Beakoss oye rr, Oc Br Hrrbtole 2, seston eta ciete tiyovre = eine nite 423—427 Wridlexs | Ficath etensrd RRP cra hn ie Hon EA ee En Oia Ley a 428 PLATES IN VOL. XII. PuaTe I, II. } Structure of Anchinia. mu. | IV. Tintinnodea. V. Hynobius lichenatus—Spelerpes peruvianus. VI. Fossil Entomostraca from Siberia. VII. Structure of Tristychius. VIII. New Earthworms. IX. Fossil Entomostraca from Spitzbergen. X. Stenopora Howsii. XI. XI. XIII. | New Sponges. XIV. | Xx Vi THE ANNALS AND MAGAZINE OF NATURAL HISTORY, [FIFTH SERIES. ] iadadacndadanddebac per litora spargite muscum, Naiades, et circitm vitreos considite fontes: Pollice virgineo teneros hic carpite flores: Floribus et pictum, dive, replete canistrum. At vos, o Nymphe Craterides, ite sub undas [It e, recurvato variata corallia trunco Vellite muscosis e rupibus, et mihi concha Ferte, Dew pelagi, et pingui conchylia succo.”’ NV. Parthenit Giannettasii Ec), 1, No, 67, JULY 1883. 1.—Waterials towards the History of Anchinia. By A. KowALeysky and J. Barrois *, [Plates I.-IIL. | Awcuinra is one of the most interesting and least known forms of the whole group of Tunicata. Hstablished by Rathke in 1833 upon notes left by Eschscholtz, this genus has since that time been studied by only a few observers; the only somewhat complete description that we know is that which Carl Vogt has left us of the Anchinia rubra, met with in very great numbers at Villafranca, where he found it floating in thousands at the surface of the sea during the months of December and January. 1. The species obtained by us at the same place also possesses a large spot of red pigment in the middle of the body, and other spots of the same colour upon each of the two large papillae which surmount the incurrent and excurrent apertures. It made its appearance at Villafranca a little later * Translated by W.5S. Dallas, F.L.S., from the ‘Journal de l’Anatomie et de la Physiologie,’ tome xix. January and February 1885. We are indebted to the kindness of M. Jules Barrois and of the conductors of the above journal for permission to have impressions of the three plates illustrating this memoir. Ann. & Mag. N. Hist. Ser. 5. Vol. xin. 1 2 MM. Kowalevsky and Barrois on Anchinia. than the time indicated by Vogt; we have only found it occasionally between the months of February and April, and each time in very small numbers. 2. The only form of Anchinia that is known (PI. IL. fig. 1) consists of fragments of zooid-bearing stolons of perfect trans- parency, which are found floating, like the Salpee and Pyro- somes, at the surface of the sea. Our materials for investigation have been rather scanty ; we have met with the Anchinia only three times, and the first time in bad weather and in a state unfit for examination. Of the two colonies afterwards captured the first alone bore, as described by Vogt, zooids in different stages of gemmation ; it is this that we have made use of in our investigations. The second presented zooids all of the same grade, in the adult state. This is a state mentioned by Rathke, but not met with by Carl Vogt. Its existence shows that there is not in this case continuous gemmation at the surface of the stolon, but an unequally rapid development of a series of previously formed germs. We have not had the opportunity of confirming the obser- vation of Vogt, who, in the great number of specimens exaroined by him, constantly found one individual surpassing the others in size and attaining as much as a centimetre in length. Nothing of this kind existed in the two specimens examined by us. 3. No observer has as yet given us any information as to the form of generation represented by the zooids attached to the surface of the stolon. Vogt did not detect in them any distinct traces of a stolon or of genital organs; one only of the specimens examined by him showed more or less oviform bodies ; but he does not come to any decided conclusion upon this point, and it is even difficult to make out exactly what the olive-green bodies indicated by him in this indi- vidual really represent. In our Anchinie we have always found perfectly visible genital organs, consisting of a testis and an ovary (PI. III. fig. 8, ¢, 0), situated at the lower part of the intestine, be- tween the heart and the peduncle, and opening by a common canal into the right expansion of the cloacal sac; it is there- fore now absolutely certain that the known Anchinia is a sexual form. 4, The stolon upon which the zooids are fixed is, according to Vogt, a cylindrical contractile canal, with thick walls, com- _ posed of longitudinal and transverse fibres, and lined within with a very fine vibratile epithelium. Unfortunately we have been unable to study the structure MM. Kowalevsky and Barrois on Anchinia. 3 of the stolonin much detail ; we have not seen muscular fibres in it; it appeared to us to be a simple hollow tube, formed of a single series of epithelial cells, and enveloped in a very thick tunic, containing here and there stellate cells. The most remarkable thing to be noted in the stolon is a series of large cells (Pl. II. fig. 1, c) superimposed upon the epithelium, and placed upon the median line between the zooids. The latter are arranged upon a somewhat irregular line and [each] implanted upon a slight projection formed by the epi- thelium of the stolon; this projection is separated from the peduncle by a double septum composed of epithelial cells ; these septa separate at the period when the bud becomes de- tached from the stolon. I. Description of Anchinia. Anchinia (Pl. III. fig. 8), like Pyrosoma and Doliolum, is a type of Tunicate in which the two apertures, incurrent and excurrent, are directly opposite to each other. The two cavities to which they give access, namely the pharyngeal sac (Ph) and the median portion of the cloaca (cm), are not, as in the Ascidia, attached to one another, but they face each other, and are situated at the two extremities (fie. 8). Between the two there is a space in which the digestive tube is lodged. In consequence of the separation of these two large cavities, the digestive tube, which in the Ascidia is situated below these cavities, is included between them in Anchinia; it is more- over surrounded to the right and left by the lateral expan- sions of the cloaca (cl), which spread over the pharyngeal sac to form the branchia. It is therefore included in a sort of case, which only communicates above and below with the rest of the general cavity. Hig. 11, which represents a trans- verse section passing through the two apertures, will serve better than any explanation to render this arrangement intel- ligible. Pyrosoma and Doliolum also present the same arrangement but with differences which it is important to note. In Pyro- soma the median portion of the cloaca is exceedingly small, in fact quite rudimentary, and out of all proportion to the pharyngeal sac, which occupies an enormous space. Its lateral portions, on the contrary, are much developed, and completely cover the whole of the pharyngeal sac, the entire wall of which is converted into branchia. In Doliolum it is quite otherwise. The lateral portions of the cloaca are rudimentary ; they do not cover the pharyngeal sac, of which the branchia occupies only the posterior por- 1 4 MM. Kowalevsky and Barrois on Anchinia. tion ; on the other hand the median portion of the cloaca attains a considerable development, and has a volume nearly equal to that of the pharyngeal cavity. Anchinia presents this interesting peculiarity :—As regards the arrangement of the great cavities and of the branchia it represents the exact intermediary between the above two great types, Pyrosoma and Doliolum. Init the median portion ot the cloacal cavity is already large, but its dimensions are still very restricted as compared with those of the pharyngeal sac ; its lateral parts are likewise better marked off from the median portion than in Doliolum, but incomparably less developed than in Pyrosoma, and only cover a small portion of the pharyngeal sac. Lastly, the branchia consists, as in Doliolum, of a single series of long clefts parallel to the endostyle; but it is wider than in Doliolum (fig. 8), and in this respect some- what approaches that of Pyrosoma. Anchiniais certainly the most complete transition type that we know between the Salpa form and the Ascidia form, re- garded as representing the two extreme types from the stand- point of the arrangement of the two great cavities. It is the most instructive form to study for any one who wishes to form a notion of these important relations. I pass now to a more detailed description :— 1. General form.—The body is very short and thickset, not at all elongated in the form of a little barrel, but extended especially in the direction of its height; its general aspect does not at all resemble that presented by the Doliola, but nearly approaches that of the lateral buds destitute of cloaca which are observed upon their tails. 2. Cloaca.—F ig. 8 shows the boundaries of the median and lateral portions of the cloaca. ‘The line /m indicates the limit of the median portion, and the line /¢ that of the left lateral expansion. ) 20 diameters. z Enlarged Fig. 2 (Pl. 1.). First stage of gemmation, seen from the ventral surface. vg. 38, The same stage in profile. Fig. 4. A more advanced stage. Fig. 5. A still more advanced stage. Fig. 6 (P1. IL.). The following stage: the branchial clefts begin to show themselves. x 90 diam. Fig. 7 (Pl. 1). A more advanced stage: the tissues have lost their embryonic character; and the creature presents a transparency like that of the adult. x 46 diam. * Loe. cit. p. 73. 20 = Mr. E. D. Cope on the Bunothertan Mammalia. Fig. 8 (P|. IIL). Adult. The letters 7s and cl represent the superior and inferior expansions of the cloaca, expansions separated at the level of the letter p, where the median portion (cm) of the cloaca comes into contact with the pharyngeal sac. The line Zz represents the boundary of the lateral portion of the cloaca, and the line / m the boundary of its median part. Fig. 9 (Pl. I1.). Transverse section of the filament of the posterior extre- mity. cell, large granular cells contained in its interior; € ¢, transparent cells which form its superficial covering ; f0, fibrous envelope ; m, section of the muscles of the aperture, which are produced on the ventral side nearly to the extremity of the fila- ment. X 150 diam. Fig. 10 (P1. I11.). Transverse section of the endostyle. Xx 250 diam. Fig. 11. Transverse section of an Anchinia at a stage a little more ad- vanced than fig. 7 and at the level of the stomach. x 30 diam. TI.—On the Mutual Relations of the Bunothertan Mammalia. By E. D. Copr*. Tue name Bunotheria was proposed by me for a series of Mammalia which resemble in most technical characters the Edentata and the Rodentia. That is, they agree with these orders in having small, nearly smooth, cerebral hemispheres, which leave the olfactory lobes and cerebellum entirely ex- posed, and in some instances the hemispheres do not cover the mesencephalum also. From the two orders in question, however, they are easily distinguished. ‘Their enamel-covered teeth separate them from the Hdentata, while the articulation of the lower jaw is different from that found m the Rodentia. It isa transverse ginglymus with a postglenoid process in the Bunotheria, as distinguished from the longitudinal groove, permitting antero-posterior motion, of the Rodentia. Such a group as is thus characterized will include two existing groups recognized as orders—the Prosimiz and the Insectivora. The latter group has always been a crux to systematists; and when we consider the skeleton alone, as from the standpoint of the palxontologist, the difficulty is not diminished. Various extinct types discovered in latter years, chiefly in the Eocene formations, have been additions to this intermediate series of forms, giving even closer relations with the orders already adjacent, ¢.e. the Kdentata, the Rodentia, the Prosimiz, and the Carnivora. As is known, the groups corresponding to these orders have been named respectively * From the ‘Proceedings of the Academy of Natural Sciences of Philadelphia ’ for 1883, pp. 77-88. Mr. E. D. Cope on the Bunothertan Mammalia. 21 the Tzeniodonta, Tillodonta, Mesodonta, and Creodonta. With great apparent diversity, these suborders show unmis- takable gradations into each other and the two recent orders already mentioned. As such I may mention Psittacotherium, which relates the Tzniodonta and illodonta, Hsthonya, which relates the Tillodonta with nearly all the other sub- orders, Achenodon, which connects Creodonta and Meso- donta, and Cynodontomys, which may be Mesodont or Pro- simian. ‘Then the existing Chiromys most certainly connects Tillodonta and Prosimiz. My original definitions of the suborders of the Mesodonta, given in vol. il. of the U.S. Geological Survey under Capt. G. M. Wheeler, p. 85, omitted the Prosimiz, and embraced a number of characters whose significance must be reexamined. Thus it is impossible to characterize the Creodonta as lacking a trochlear groove of the astragalus, in view of the form of that element in Mesonyx and Mioclenus, where the groove is more or less distinct. It is impossible to distinguish the Insectivora from the Creodonta by the deficiency of canine and large development of incisor teeth. In Rhynchocyon the canines are large and the superior incisors wanting, while in Centetes the arrangement of these teeth is precisely as in the Creodonta. As to the large Achewnodon and other Arctocyo- nid, I find no characters whatever to distinguish them from the generally small Mesodonta. In view of these inconsistencies I have reexamined the subject, and find the following definitions to be more nearly coincident with the natural boundaries of the divisions of this large order. ‘The importance of the character of the tritu- bercular superior molar has recently impressed me (see ‘ Pro- ceedings of the Academy,’ 1883, p. 56), as it had previously done Prof. Gill. This zoologist has already distinguished two divisions of the Insectivora (without the Galeopithecide) by the forms of the superior molar teeth. ‘The first possesses quadritubercular molars above, the second tritubercular. That these types represent important stages in the develop- ment of the molar dentition I have no doubt. These cha- racters far outweigh in importance those expressing the forms of the skull, matters of proportion only, with which a few systematists unnecessarily overload their diagnoses. Such characters are of little more than specific value, and serve to obseure the mind of the inquirer for a true analysis. ‘They may be used empirically, it is true, to determine relationships when the diagnostic parts are wanting. I propose to transfer the Insectivora with tritubercular superior molars to the Creodonta, in spite of the fact that some 22 Mr. E. D. Cope on the Bunotherian Mammalia. of them (Jfythomys, Solenodon, Chrysochloris) have but weakly developed canine teeth, and Chrysochloris has large incisors. As an extreme form Hsthonyx will follow, standing next the Tillodonta. It will then be necessary to transfer the Arctocyonide and all the Mesodonta to the Insectivora, where they will find affinity with the Tupzide. These have well-developed canines and small incisors, as in the extinet groups named. ‘The Chiromyide must be distinguished from all the other suborders, on account of its rodent-like incisors combined with its lemur-like feet. The characters of the six suborders will then be as fol- lows :— I. Incisor teeth growing from persistent pulps. Canines also growing from less persistent pulps, agreeing with external incisors in haying mo- . lariform crowns ...... Set Oe s Oats eee er 1. Teniodonta. Canines rudimental or wanting; hallux not opposable...... oF caldera ites eons op ee aeTic Jo Ne 11. Tillodonta. Canines none; hallux opposable ............ 1. Daubentonioidea. Il. Incisor teeth not growing from persistent pulps. Superior true molars quadrituberculate ; hallux GPPOSADIE ® hieio es 5 Sracuis: era catsiots ee ene eee Iv. Prosimie. Superior true molars quadrituberculate ; hallux BIO LAG PPOSHDIO oS ccrs ore csesste eye Siererele mis eas reve v. Insectivora. Superior true molars trituberculate or bituber- culate *; hallux not opposable ............ vi. Creodonta. While the above scheme defines the groups exactly and, so far as can now be ascertained, naturally, I do not doubt that future research among the extinct forms will add much necessary information which we do not now possess. It is possible that the group I called Mesodonta may yet be distinguished from the Insectivora by characters yet unknown. But I cannot admit any affinity between this group and any form of “ Pachyderms,” as suggested by Filhol, or of Suil- lines, as believed by Lydekker ft. Such suppositions are in direct opposition to what we know of the phylogeny of the Mammalia. These views are apparently suggested by the Bunodont type of teeth found in various Mesodonta; but that * The internal tubercle is wanting in the last two superior molars in Hyenodon. ‘This genus, of which the osteology remains largely unknown has been stated by Gervais to possess a brain of higher type than the Creodonta, Prof. Scott, of Princeton, however, is of the opinion that this determination is erroneous, and that Hy@nodon is a true Creodont in this and other respects. If so, the genus will perhaps enter the Amblyctonide. + Memoirs Geological Survey of India, ser. x. 1883, p. 145. Mr. E. D. Cope on the Bunotherian Mammalia. 23 character gives little ground for systematic determination among Hocene Mammalia, and has deceived paleontologists from the days of Cuvier to the present time. The only con- necting-point where there may be doubt as to the ungulate or unguiculate type of a mammal is the family Periptychide, of the suborder Condylarthra. The suborder Hyracoidea may furnish another index of convergence. The families included in these suborders will be the fol- lowing :— Tantoponra. Calamodontide, Ectoganide. Tittoponta. Tillothervide. DAUBENTONIOIDEA. Chiromyide. Prosimim. Tarstide, (?) Anaptomorphide, (2) Mixo- dectide, Lemuride. Insectivora, Soricide, Lrinacetde, Macroscelide, Tupaide, Adapide*, Arctocyonide. Creoponta. Yalpide, Chrysochloridide, Esthonychide, Centetide (= Leptictide olim), Oxyenide, Miacide, Amblyctonide, Mesonychide. I at one time called this order by the name Insectivora, a course which some zoologists may prefer. But a name should as nearly as possible adhere to a group to which it was first applied, and whose definition has become currently associated with it. Such an application is correct in fact, and is a material aid to the memory. ‘There are various precedents for the adoption of a new general term for a group composed of subordinate divisions which have themselves already re- ceived names. In order to determine the number of internal tubercles in some of the Insectivora, so as to ascertain the affinities of some questionable genera, it 1s first necessary to examine the homo- logies of the cusps of the molar teeth. The opossums are characterized by the presence of three longitudinal series of tubercles on the superior molar. The homologies of these cusps are rendered clear by the character presented by the fourth superior premolar, where the anterior intermediate is wanting. ‘lhe external cusps are really such, and are not developed from a cingulum external to the true external cusps, * Two species of Pelycodus must be removed from this genus and family and be placed in the Creodonta with Mvoclenus. They are the P, pelvidens and P. angulatus, which have the posterior inner tubercle of the superior molars a mere projection of the cingulum. I place them in anew genus, which differs from Mcoclenus in the possession of an internal cusp of the fourth inferior premolar, under the name of Chriacus, type C. pelvidens, 24 = =Myr. E. D. Cope on the Bunothertan Mammalia. as appears at first sight to be the case with such animals as the Talpide. The intermediate cusps are really such, although the posterior looks like the apex of a V-shaped external cusp. In Perathertum the external cusps are smaller than in Di- delphys, and the intermediate V’s so much better developed that the type is much like that of the Talpide, to whose neighbhourhood I originally referred it. This leads to a consideration of the question of the homo- logies of the cusps in the genera of the old order of Insectivora proper, and of the Creodonta. Mr. St. George Mivart has briefly discussed the question, so far as relates to the former group*. He commences with the primitive quadrituberculate type presented by Gymnura and Erinaceus, and believes that the external cusps occupy a successively more and more internal position till they come to be represented by the apices of well-developed V’s, as in the ungulate types. The V’s are well developed in several families; and in Chrysochloris the two V’s are supposed to be united and to constitute almost the entire apex of the crown, while in Centetes the same kind of V forms a still larger part of the crown. I believe that these conclusions must be modified, in the light of the characters of various extinct genera and of the genus Didelphys. In the first place, there is an inherent im- probability im the supposition that the external V’s of the superior molars of the Insectivora have had the same origin as those of the Ungulata. The movements of the jaws in the two groups are different, the one being vertical, the other partially lateral. In the one, acute apices are demanded ; in the other, grinding faces and edges. We have corresponding V’s in the inferior dental series, and we regard those as pro- duced by the connexion of alternating cusps by oblique ridges. In homologizing the superior cusps we have as elements two external, two intermediate, and two internal cusps. The first are opposite the external roots, and the anterior internal is op- posite the internal root. First, as regards Centetes and Chrysochloris. Besides the strained character of the hypothesis that supposes the V-shaped summit of the crown to represent two V’s fused together, there is good evidence obtainable in support of the belief that the triangle in question is the usual one presented by the Creodonta. This clearly consists of the two external and the anterior internal cusps united by angular ridges. ‘The form is quite the same as in Leptictis and Ictops, and nearly that of Delta- * Journal of Anatomy and Physiology, il. p. 138, figures. Mr. E. D. Cope on the Bunotherian Mammalia. 25 thertum, where the external cusps are present. Centetes and Chrysochloris only differ from these in that the internal cusps are wanting. In addition, the latter genus presents a rudi- ment of the posterior inner tubercle, as is seen in Deltathertum. An explanation similar to this is admitted by Mr. Mivart to apply to the cusps of the inferior molar of Centetes. It remains to ascertain whether the cusp in this genus, Chrysochloris, &c. represents an intermediate or not. Secondly, as regards the Talpide and Soricide, where the external V’s are well marked. If we examine the external cusps in the genus Didelphys, we find that the posterior one becomes gradually more anterior in its position, until on the second true molar it stands largely above the interspace be- tween the roots instead of over the posterior root. It will also be seen that the anterior intermediate tubercle is distinct and of insignificant proportions, while the posterior intermediate is large and is related to the posterior external as is the apex of a V to its anterior base. In this arrangement I conceive that we have an explanation of the V’s of the Talpide and Sori- cide. The first true molar of Scalops is a good deal like that of Didelphys; but the anterior cusp is larger and there is no anterior intermediate cusp, while the posterior external is of reduced size. ‘The posterior V is better developed than in Didelphys but is composed, in the same way, of a posterior intermediate cusp, and a posterior external with a posterior heel. ‘These are united by stronger ridges in Scalops, Con- dylura, and Blarina than m Didelphys. On the second true molar in Scalops a V represents the anterior external cusp of the first true molar. Whether this V has a constitution like the posterior one, 7. e. is composed of external and intermediate cusps joined, is difficult to determine; but it is probably so constituted. It seems to be pretty clearly the case in Blarina, where the fourth premolar and first true molar may be com- pared, with a resulting demonstration of the correctness of this view. In Condylura the V’s have become more deve- loped and the external cusps reduced, so that the analysis is more difficult. This interpretation applied to Urotrichus and Galeopithecus gives them quadrituberculate molars, not trituberculate, as determined by Mivart. Mystomys is tritubercular. The intermediate tubercles are present, but are imperfectly connected with the external, so that V’s are not developed (wide figures of Mivart and Allman). This genus offers as much confirma- tion of the homology here proposed as do the opossums; but it differs from the latter in having the anterior intermediate tubercle the larger, instead of the posterior, Mystomys and 26 Mr. H. J. Carter on the Microscopic Solenodon also confirm my determination of the homologies in Centetes*. In conclusion I give the following synoptic view of the constitution of the superior molar teeth in various genera of the Bunotheria. CUSPS PRESENT. External, intermediate, two internal. Adapidie. |Tupeeidee. \Galeopithecide. Soricidie. Urotrichus. | | | External, no intermediate, two internal. Gymunura. Erinaceus. Macroscelidide. External, intermediate, one internal. | Mystomyidee. | Mioclezenus. Miacis. Talpidee. \(Didelphys.) (Canis.) \Oxyeena. (Chriacus. ‘Deltatherium. |Esthonyx. External, no interme- diate, one internal, Mesonyx. Leptictis. Stypolophus. (2nd internal rudimentary ). No external, no inter- mediate, two internal. Chrysochloris (2nd internal rudimentary). Solenodon (ditto). No external no interme- diate, one internal Centetes. I1l.—On the Microscopic Structure of thin Slices of Fossil Calcispongie. By H. J. Carter, F.R.S. &e. In the “ P.S.” which I hastily added to my last “ Observa- tions on the so-called ‘ Farringdon Sponges’ (Calcispongie, Zittel),” it is stated that Dr. Harvey B. Holl had kindly sent me four slides, testifying respectively to two facts, viz. 1st, that the spiculation of Verticillites anastomans was that of a Calcisponge, to me size”? with that of Grantia compressa; and 2nd, that it was confronted by a crust of pinlike spicules with their heads outwards; and at the conclusion, that I had no¢ seen the latter in my specimens of Vertdicillites anastomans from Farringdon in Berkshire. Wishing to confirm this, I obtained through Dr. Holl’s kindness his entire specimen, and having made two or three 6c precisely like and almost identical in * This view was first advanced by the writer in the Annual Report U.S. Geol. Sury. Terrs. 1873-74, p. 472. Structure of Fossil Calcispongic. 27 slides from it, found in all what I have stated; while, seeing that the specimen was identical with one of my own from Far- ringdon, I did the same with this with the same result; but when thus engaged I saw that I had specimens of another form in my collection, and that this also presented the pinlike spicules. It was then evident that there were two, viz. Dr. Holl’s and another, and that they chiefly differed in the form of the siphonal cloaca which passes through the centre of each septum, like that of an Orthoceras, only with the convexity of the septa reversed (that is, directed upwards or outwards) in Verticillites. In Dr. Holl’s specimen this passage is reduced toa marginated circular hole of intercommunication in the septa which separate the chambers; while in the other form it is a continuous tube or cylinder communicating with the chambers respectively by holes in its s¢des, which thus, through this canal, establish a communication with the exterior. On reference to Dr. Gustav Steinmann’s figures (“* Pharetro- nen-Studien,’’ Neues Jahrbuch f. Mineral. Geol. u. Palionto- logie, 1882, 11. Bd. Taf. vi. u. vii. figs. 5,6 u. 1 respectively) I see that Dr. Holl’s species has been called “ helvetica”’ by De Loriol (Urgonien infér. de Landeron, p. 65, t. v. figs. 4— 11); while the other form had long since received the name of “ Verticillipora (Verticillites, Detr.) anastomans” from Man- tell (‘ Wonders of Geology,’ p. 636, fig. 3, &c.). The pinlike spicules, however, are present in doth, and ar- ranged in the manner of a funnel, with the spout inwards or continuous with each external aperture of the radial canals, as may be proved by making a horizontal and vertical section of the wall respectively, when the full length of the pinlike spicules is seen in the former sloping inwards towards the canal, and their truncated ends in a circle surrounded by the triradiates in the latter, while by making one horizontally through the septum and the wall together both may be seen at once. ‘The pin spicules, like the triradiates, are dissolved by diluted nitric acid, although generally preserved in form when that of the triradiates has almost entirely disappeared. It is very probable that Dr. Holl’s specimen came trom the same neighbourhood as my own; but, be this as it may, it would be desirable to ascertain if the pinlike spicules are absent in the species from the Jura and elsewhere out of Eng- land, as they are in Dr. Hinde’s Verticillites D’ Orbignyi, which came from the Upper Greensand at Warminster in Wiltshire, within twenty-four miles of Farringdon. The next point to which I would direct attention is the change which takes place in the spiculation of the Calcispongiz during fossilization, to which I have also hastily alluded 28 Mr. H. J. Carter on the Microscopic in the following “ footnote” to my above-mentioned paper in the ‘ Annals,’ viz. :— “Can it be possible after all, that this concentric lamina- tion is mineral and not organic—that is, that the calcareous layers are but a reproduction in form of the original spicules, which, during fossilization, have become dissolvedand furnished this solution for the new structure, as often seen in the chalce- donization of the vitreous sponges, or as agatoid layers round a grain of extraneous matter? ‘lhe examination of another slice of my specimen of Sestrostomella from the Jura strongly inclines me to this view”’ (‘ Annals,’ ser. 5, vol. xi. p. 35). Thus influenced, I lost no time in endeavouring to confirm the inference by grinding down slices of several species of fossil Calcispongiz to a minimum of at least 1-500th of an inch, or semitransparency, viz. Verticillites anastomans and helvetica, Peronellu dumosa, Oculosponyia dilatata, Elasmo- stoma acutimargo, and two or three others, when I came to the following conclusions :— 1. That during fossilization, the organic matter of the spicule disappearing, the mineral matter, thus deprived of its cement, is set free. 2. That while this is taking place the forms of the spicules are more or less destroyed and the mineral matter more or less passes into solution. 3. That the forms of the spicules thus more or less destroyed run into each other so as to assume shapes totally different from what they were originally, while the rest of the caleare- ous material in a state of solution becomes deposited in the form of fibre composed of one or more concentric layers en- closing the lines of spicules. 4, That although the slice when reduced to extreme thin- ness may present no distinct tri- or quadriradiates, yet one or more perfect ones may have come into view during the latter part of the reduction, when, atter every two or three strokes of the grinding, the slice should be transferred to the field of the microscope, lest the spicule be rubbed off altogether. Hence the advantage of grinding down the slice one’s self, otherwise such important facts might pass unnoticed. 5. That if the tri- or quadriradiate of a Calcisponge cet. par. is thus seen, this should be sutticient to prove the nature of the fossil, although the next stroke of the grinding may destroy it, which is often the case. Observations. It is, however, the running together of the lines of the Structure of Fossil Calcispongice. 29 original tri- or quadriradiate spicules which leads, in all in- stances that I have examined, to the branched, forked, and other forms that resemble the spiculation of a Lithistid sponge, especially after the slice has been reduced to the lowest degree (that is, to semitransparency). Hence, whenever I have been so fortunate as to see even one undoubted tri- or quadriradiate of a Calcisponge, although, as before stated, it may have dis- appeared in the subsequent grinding, I have felt as convinced that the fossil was a Calcisponge as that the fantastic forms which accompanied it were spurious ; so that now when I come toa perfect tri- or quadriradiate of the kind mentioned, I stop grinding and mount the specimen for preservation and more deliberate examination. Process of Grinding down a Slice of a Calcareous Fossil for Microscopicol Kxamination. Take about one part of half-dry Canada balsam, and place it on the centre of a glass slide; heat it until melted over a spirit-lamp with about half an inch vertical flame, moving the slide backwards and forwards to prevent the latter from cracking ; add two parts of shellac ; and when the whole has bubbled up, stir it with the point of a needle so as to mix well, and spread it altogether over a little more of the glass than the size of the slice to be reduced. Previous to this, cut off with a watch-spring or very fine saw fixed in an iron bow-frame (all of which may be obtained from an ironmonger at a very small charge) the slice to be ground down; and if there be much siliceous matter in the fossil, the saw (which is very cheap) may be sacrificed by the addition of emery powder and water to the groove, as this accelerates the cutting. (Of course where a machine with horizontal turning-wheel is possessed, such as is used for cutting siliceous fossils, flint, &c., this is the quickest and most economical way to obtain the “ slice,’’) Having thus obtained it, so far prepared, rub one side (viz. that to be examined) down to scratchless smoothness on a schoolboy’s slate or very fine honestone with level surface, to effect which it is absolutely necessary that all the materials should be entirely freed by washing from every particle of emery or siliceous mineral that may happen to be present ; otherwise the calcareous surface. will become almost irre- mediably furrowed. Next dry the slice on a tin or paper tray placed inside the fender by the fire, where it can remain until the next part of the process is completed. 50 Mr. H. J. Carter on the Ovigerous Layer of Now remelt the material on the glass slide as before ; and when sufficiently fluidified to present a uniformly level surface (but not burnt, for this would destroy the tenacity of the cement and thus give it a crispness which, by cracking, would defeat all attempts at further reduction), quickly transfer the warmed slice (which should now be close at hand) to it, while with a little pressure the ‘ smoothed”’ surface is brought into direct contact with that of the glass. Thus let it remain on the table where thisis done until the glass feels cold to the touch. After this reduce the slice to the thinness of a wafer over a very fine vertical rotating grinding-stone, or on a copper plate with emery powder and water, horizontally. Now wash it well in water, and, placing the slide on a piece of buckskin leather spread on the table or over a level surface (to keep it from slipping) with the slice uppermost, continue the reduction in water with a piece of very fine siliceous limestone, that may be obtained from a statuary, of a convenient form (that is, one which will admit of the surface of the slice coming into direct and continuous contact with that of the limestone), with which it should be horizontally rubbed until reduced to the required thinness, which must_ be ascertained by repeatedly transterring the slice to the field of the microscope with an inch object-glass and high ocular, The nearer this thinness is approached the oftener this trans- fer should be made, washing the slice by dipping the slide into a bowl of water each time that it is examined. When sufficiently reduced, wash the slide as before, and stand it up to drain until the slice is perfectly dry. Then cover with benzol, followed by balsam and thin glass, for preservation and more deliberate examination. I make no apology for introducing these remarks, as the “ process,” although open to criticism and improvement no doubt, answers the purpose; and while inexperienced I myself should have been very glad of such aid. Dr. Holl suggested to me the use of shellac, which is the most valuable hint that I have received. 1V.—On the Presence of Starch-granules in the Ovum of the Marine Sponges, and on the Ovigerous Layer of Suberites domuncula, Nardo. By H. J. Carter, F.R.S. &e. Ir was but a short time since that I pointed out another in- stance of a structure like thai of the cellular tissue of plants, Suberites domuncula, Nardo. 31 situated around the statoblast of freshwater sponges (‘ Annals,’ 1882, vol. x. p. 367) ; the presence of starch-granules had been described in 1856, although not figured until 1859; and now I have to announce the latter also in the ovum of the marine sponges. As this was brought to my notice by cutting up a fragment of the ovigerous layer of Suberites domuncula into small pieces, when, by pressure, both oil-globules and starch- granules made their appearance among the granular contents of the ova, I will particularly describe this layer before com- paring these ova with those of other sponges. Familiar to naturalists as Suberites domuncula, Nardo, ap. Schmidt, 1862 (Spong. Adriatisch.), = Hymeniacidon suberea, Bowerbank, 1866 (Mon. Brit. Spong. vol. 11. p. 200), has been for many years past, viz. from Aldrovandus, at the beginning of the 17th century (Johnston, Brit. Spong. p. 142), down to the present time, although not recognized as a sponge until Col. Montagu described it as such from specimens dredged on the coast of Devonshire circa 1812 (Werner. Mem. Edin. 1818, vol. ii. p. 100), no one appears to have noticed the striking manner in which its ova are deposited in a layer on that part of the hard object (generally a dead shell} over which it may have grown. On the 6th January 1870, after a storm, I picked up on this beach (Budleigh-Salterton, South Devon) two specimens, and on ihe 4th September 1877 upwards of 150 were brought to me from the dredgings of a ‘ trawler” about 20 miles off this shore, all of which had grown on dead shells of a similar kind, viz. Turritella and small Buccinwm, tenanted either by a hermit crab (Pagurus) or annelid. All, oras many as I have examined, present the same kind of ovigerous layer, in which all the ova are in the same stage of development; so that we may infer, from the dates above mentioned and what will be stated hereafter, that throughout the year these sponges, if containing a dead shell or any similarly hard object, will have upon it a similar ovigerous layer. Like most of its kind, too, Suberites domuncula not only grows over the dead shell, but as it grows encloses a large quantity of the fine detritus of the sea-bed in which it may have lived; so that it is impossible to free the smallest por- tion from this foreign material, and it is on this account equally impossible to obtain a satisfactory view of the finer elements of which the sarcodic substance of the sponge itself is com- posed. Kach specimen appears to be but a single individual (“ person,” Hiickel), as each has only a single ragged vent 32 Mr. H. J. Carter on the Ovigerous Layer of situated on the most pendent or prominent part, which is the outlet of a well-developed excretory canal-system, whose branches pervade the extremely fine and compact structure of which the sponge is otherwise composed. The pinlike spicules &c. and the ovigerous layer that I am about to describe are also particularly evident; but as the sponge generally has been heretofore repeatedly noticed with the exception of this layer, I shall henceforth confine myself to a description of the latter only. If a vertical section of one of these specimens be made, so that the incision may fall perpendicularly and longitudinally on the shell over which the sponge may have grown, and the two portions forcibly separated trom each other, so as to ex- pose the shell beneath (say a Turritella about 14 inch long), a yellowish chitinous layer composed of ova closely packed together (not unlike the nidamental layer of a mollusk) will be left upon the shell, corresponding in extent to the amount of the shell covered by the sponge, whether this be a part or the whole, and adhering so strongly that the whole of the sponge-substance may be washed off with a brush without dis- turbing the attachment (fig. 3). On the other hand, sup- posing that the sponge, as is commonly the case, be attached to the whole length of the TZurritella and the specimen (having been preserved in a wet state) is put into dilute nitric acid, the shell part will be entirely dissolved away, leaving the ovigerous layer in this instance attached to the sponge, when a similar section with a sharp thin knife may be made to pass through both the sponge and the ovigerous layer together ; and thus, by examining the object in water under a microscope, the thickness and structure of the latter may be easily ascertained. The ovigerous layer may then be observed to be composed of a yellowish tough chitinous stratum of ova in juxtapo- sition, but only one ovum deep or thick (fig. 2), of which the part that was in contact with the shell is flat, thin, and even (fig. 2,4), but that towards the sponge thick and granulated by the convexities of the layer of ovarian cap- sules, which, from being compressed together, vary slightly in height, size, and shape, so that, although generally the stratum or ovigerous layer is only one 200th of an inch thick, the thickness towards the sponge is so far rendered irregular (fig. 2, a), while the horizontal diameter of the ova when viewed in a flat position on the sponge side is found to vary from the 180th to the 90th of an inch (fig. 8); hence the ovum, being flat below, convex above, and rendered more or less polygonal laterally by horizontal compression, fails to Suberites domuncula, Nardo. 33 present that spherical form which it would do if, as in other cases, it had been isolated in the midst of the sponge-tissue. Taking the elements of the ovum one by one from without inwards, it will be found to consist of a thick chitinous capsule followed by a delicate membrane filled with the yelk. The capsule, as before stated, is convex towards the sponge, flat towards the shell, and polygonal laterally, presenting on its convexity a great number of minute circular granules or points arranged more or less hexagonally, more or less pro- jecting beyond the surface, often possessing a punctum in the centre, and always connected with each other by a fold of the surface, so that it presents under high microscopic power a reticulated appearance (figs. 3, a, and 4). This part of the capsule is very thick when compared with the side towards the shell, being composed of five or more chitinous layers, amounting in all to 1-3000th inch, while the flat side hardly amounts to more than one of these layers. Interiorly it is smooth, where it is in contact with the delicate mem- brane investing the yelk, and appears to be uniformly closed on all sides; so that no aperture whatever could be detected in it. The yelk, on the other hand, surrounded by this “ delicate membrane,” which is hardly demonstrable from its trans- parency and thinness, consists of spherical refractive granules about 1-12000th inch in diameter, among which are a great many oil-globules and starch-granules, the latter of a greyish- white colour, more or less oval in form, flat, and presenting a crack-like translucency in the centre, varying in size under 1-600th inch in diameter and becoming of the usual opaque blue colour under the influence of iodine, when they strikingly contrast with the whiteness of the yelk-granules generally, which do not become so coloured. Such is the composition of this ovigerous layer, and such the characters of the contents of the ova in every instance that I have examined ; so that it may fairly be assumed that under these circumstances none ever get beyond the granulation of the yelk in this position, whatever they may do afterwards when impregnation and the duplicative subdivision of the yelk destroys the individuality of the yelk-granules and leads on to the development of the embryo—a state which I have not witnessed, nor do I know where to find; but as the ovigerous layer is only to be seen over the surface of the hard objects enclosed by the Suberite so long as they exist, and no trace of such a layer or any ova can be discovered after the shell has disappeared, even when its mowld still remains empty, which is often the case (as proved by a specimen where the Ann. & Mag. N. Hist. Ser. 5. Vol, xii. 3 34 Mr. H. J. Carter on the Ovigerous Layer of upper half of the Zurritella on which the sponge had grown remains with the ovigerous layer still on it, while the lower part has disappeared and left not a trace of ova or the ovigerous layer behind, where both originally existed (fig. 1), and in another, where the original shell has passed away and a smaller one has been enclosed, apparently for the purpose of receiving a new ovigerous layer), it seems not impossible that impregnation and the further development of the ovum may take place with the disappearance of the shell, when the embryo at least could easily escape through that part of the capsule which was in contact with it, and which I have stated to be so extremely thin (fig. 2, d). Let us now turn our attention for a few moments to the ova of other marine sponges, to see how far they agree with those of Suberttes domuncula ; and selecting Lsodictya simulans, Bk., for this purpose out of several ova-bearing ones that I have, preserved in spirit, the ova will be found to be congregated in the sponge towards the base or oldest part, but not attached to the rock on which the sponge may have grown, as in uberites domuncula. While thus isolated they present a sphe- rical form so long as the yelk has not passed into the fully developed embryo; but when this is completed the embryo bursts through the delicate capsule which enclosed it, and then assumes the form of a conical shot or elongated cone with a little tuft at the obtuse end (the long cilia). Under the former or spherical condition, in my specimen, the grumous or clotted state of the contents and presence of spicules already show that the originally granular state of the yelk has been trans- formed through duplicate subdivision with its consequences, into the coming embryo, and thus the presence of starch, although evident under the use of iodine, is now very trifling, showing that in the egg of the Suberite, as in the seed of plants, it is abundant at the commencement and disappears in the usual way under germination. The same observations apply to the ova of Halisarca lobu- laris, Aplysina corneostellata (Darwinella aurea), Esperia, and Halichondria sanguinea, Johnst., so that we here see the animal nature evinced in spite of the resemblance of the ova of sponges to the seed of plants ; for while the sponge-embryo develops a root for fixation only, and a superstructure tor supporting organisms that take in crude material for food, that of plants develops a root for nutrition as well as fixation and a leafy superstructure, viz. the “ plumule,” which grows by endosmosis through the spongioles at the ends of the radicles. Having already gone into the subject of impregnation in Suberites domuncula, Nardo. 35 the Sponges (‘ Annals,’ 1882, vol. x. p. 364), Ihave only to add here that, accompanying the ova of Aplysina corneostellata especially, which are about 1-120th inch in diameter, there are in my specimen many smaller spherical bodies averaging only 1-360th inch, which in size do not appear to be a second set of ova, although when dyed with aniline red they all (both ova and these bodies) become equally tinged and much more so than the other parts; but being respectively surrounded by a capsule formed of granuliferous cells, 1t 1s almost impossible to say what appearance their respective contents otherwise present. I think I can see the same also among the ova of Isodictya simulans, where the granulated appearance of thedr contents is not obscured by a capsule of this kind; and certainly in a thin slice of Grantia compressa, whose spongozoa in the living state were successfully fed with indigo, so that all the other elements (viz. larva, ova, and these granuliferous cells) remain uncoloured, while the blue spongozoa mark out the ampullaceous sacs with a sharpness which prevents all confusion ; but whether these granuliferous bodies were spermatic or not I am unable to decide. It may not be unworthy of remark here, that while examining the freshwater sponges of Bombay, in 1856, I noticed granulife- rous cells which seemed to me to be spermatic, and thus de- scribed them “ provisionally’? under the head of “ sperma- tozoids”” (‘ Annals,’ 1856, vol. xviil. p. 227). Lastly, another instance of the presence of spermatozoa In sponges has lately been added by Dr. N. Poléjaeff, of the University of Gratz, which was obtained from an examination of Sycandra raphanus, Hickel, in the living state, by making very thin slices and examining them under a high microscopic power, afterwards followed by the application of osmic acid and alum-carmine, to render the tail or cilium more evident (“ Ueber das Sperma und die Spermatogenese bei Sycandra raphanus, Hickel,” Separat-Abdruck aus dem lxxxvi. Bande der Sitzb. der k. Akad. Wissensch. 1 Abth. Nov. Heft, Jahrg. 1882; read 16th Nov. 1882). But still there is no character given to the spermatic cell, as I have before noticed, by which it may be satisfactorily recognized by the inexperienced student, if, indeed, there be any such ; and, so far as the granu- lation goes, it is as conjectural to me now as it was in 1856. Allusion is made (p. 4) to my also conjectural figures of the spermatozoon in Grantia compressa (‘ Annals,’ vol. xiv. p- 108, pl. x. figs. 21-23), which are so much more like the monociliated cells of the larva at a very early period than the spermatozoa of Sycandra raphanus represented by Dr. Polé- jaeff, that I am now more inclined than ever to regard them as such. 3* 36 On Suberites domuncula, Nardo. The ova of sponges in colour generally follow that of the parent sponges themselves, especially towards maturity, when this becomes more intense, and thus they contrast strongly with the rest of the substance. The ovabearing specimens which I possess are :—Halisarca lobularis, obtained from this shore in July 1874; Aplysina corneostellata, from Vigo Bay, by Saville Kent, F.L.S. &e., June 1870; Lsodictya simulans, from this shore (here the ovum is white), July 1874 (at this time also [found Esperta and Halichondria sanguinea nan ova- bearing state, but did not preserve any of them); lastly, Grantia compressa, trom this shore, May 1871, viz. those individuals which were successfully fed with indigo. Dr. Polgjaeff does not give the date of his observing the sperma- tozoa in Sycandra raphanus, although, from his paper having been read in the month of November, it may be inferred that this took place during the preceding summer. It is desirable to add the dates of such observations, because they may not only be a guide to others, but finally fix the period of this mode of reproduction in the species. EXPLANATION OF THE WOODCUTS. Fig. 1. Suberites domuncula, Nardo, natural size. Section of, showing :— aaa, sponge; 6b, cavities left by the lower whorls of the en- closed shell (Twrritella), which have disappeared ; c, remaining portion of the shell, covered with the ovigerous layer. Fig. 2, The same. Fragment of vertical section of ovigerous layer, showing :—a, convexities of capsules towards the sponge; 6, flat membrane covering the shell. Scale about 1-24th to 1-1800th inch. Fig. 3, The same. Fragment of ovigerous layer viewed from the sponge side, showing the juxtaposition of the ova: a, ovum, on which the granulation of the surface is depicted. Same scale. Fig. 4. The same. Fragment of the granulated surface, much magnified. Scale about 1-24th to 1-GO00th inch. é Microscopie Seaual Characteristics of Oysters. 37 V.—The Microscopic Sexual Characteristics of the Ameri- can, Portuguese, and Common Edible Oyster of Europe compared. By Joun A. RyDER*. In the issue of ‘ Forest and Stream’ of November 30 just past, in an article by the writer, page 351, middle column, it is remarked :—‘I regard Davaine’s observations upon the histology of the reproductive organs [of the European oyster] as of little value, being made before the introduction of im- proved methods of investigation. His figures of the finer structural details have apparently been made from crushed fragments.” In passing this judgment upon Dr. Davaine’s work I have been severer than the state of the case demanded, as will be seen in the sequel, though I do not yet admit that his methods of research were what they should have been, for until now we have had no adequate description of the structures in question. Until recently I have maintained with reservations that the sexes in the European oyster were probably separate, as in the American; more recent investi- gation with more refined methods have proved to me that in this I was in error. In my article in ‘ Forest and Stream’ I also took occasion to refer to a statement in Gegenbaur’s ‘ Klements of Comparative Anatomy,’ English edition, p. 380, where he says :—“ In the oysters we find an intermediate step toward a separation of the sexes, inasmuch as these organs are not active at the same time in the same individual; but the male and female organs alternately so.” The writer, in com- menting upon the above, then wrote, “ This quotation tacitly admits the unisexuality of the Huropean oyster, to which it evidently refers. The last part of the remark, however, is founded upon the slenderest kind of evidence—in fact, upon no evidence except a surmise, as such an alternate activity of the two parts is improbable | for obvious reasons | ; besides, it is not possible to demonstrate such an alternation of sexual activity in the same individual. As every one knows, the soft parts of an oyster cannot be examined without opening the shell, which necessarily makes the needed second obser- vation to confirm this alleged alternation of sexual activity a physical impossibility.” Iam now in a position to go still further, and to assert that the first part of the quotation from Gegenbaur is also erroneous, because we may find both eggs and spermatozoa in the same follicle at the same time. * From the ‘Bulletin of the United-States Fish Commission,’ March 14, 1883, pp. 205-215. 38 Mr. J. A. Ryder on the Microscopie What, then, is the true state of the case? This query we propose answering ; but before we set out it will be necessary to give some account of the methods of investigation used in order to arrive at a definite conclusion. Thin sections of those portions of the animal in which the reproductive struc- tures are lodged are of the first importance. After trying various methods, which were found for the most part unsatis- factory, the preparation of sections was finally conducted as follows:—After the soft parts were removed from the shell they were thrown into a chromic acid solution of from one to two per cent., in which they were allowed to remain for several days; and in some cases the hardening solution was even re- newed, This was done in order that the hardening agent might act upon the whole of the soft parts and harden them throughout ; unless the chromic acid is allowed some time to act upon the entire animal, it will not be uniformly hardened, the centre of the body remaining soft. After hardening, the animals should be thoroughly washed and soaked in water for a couple of days, to remove all traces of the acid before they are finally put into alcohol for permanent preservation. Hardened material so preserved will make good sections months afterwards. Portions of the body-mass of different individuals should then be cut out; it is best to cut up the body into thick slices or blocks in a transverse direction, large enough to be conve- niently held between the fingers. It was also found advisable to take such thick slices of the hardened body-mass from several individuals, since it was discovered that scarcely any two had the reproductive glands developed to exactly the same degree of maturity. ‘This point is important, as it bas enabled us to follow up the development of the reproductive organs in the connective tissue which invests them. After considerable experiment and disappointment in the effort to imbed these thick hardened slices so as to cut sections with the microtome, the method of imbedding was abandoned alto- gether. ‘he thick blocks or slices were entirely freed from alcohol by soaking in water for a day, then removed, after drying them off as much as possible with blotting-paper or a soft linen cloth, to a thick solution of gum arabic, in which it is best to allow them to remain from twenty-four to forty-eight hours, so as to be thoroughly saturated. The superfluous gum may then be poured off and the blocks of tissue, soaked as they are with the gum, covered with strong alcohol. In twenty-four hours the blocks will be found hard enough to cut. ‘The blocks of hardened tissue are simply held between the thumb and fore finger, and thesections made with a section- Sexual Characteristics of Oysters. 39 knife with the free hand. When cutting sections it is neces- sary to keep the knife well wetted with alcohol, so that the sections may readily slide off on the upperside of the blade. Water should not be used to wet the knife, as it would get on the block of tissue, dissolve the gum, soften the surface to be cut, and injure the succeeding sections. ‘The sections are lifted from the knife as fast as cut, with a camel’s hair pencil, and\ chrown into a dish of water, in which the gum will dissolve out in a few minutes. The sections are then ready to be stained; and in order to clearly differentiate the herma- phroditic character of the reproductive glands of Ostrea edulis, a special staining reagent must be used. The one which gives the best results and acts most quickly will be given here. Equal parts of dense alcoholic solutions of safranin red and methyl green * are poured together and diluted with about eight times their combined volumes of water, producing a dark purplish solution of about the colour of claret wine. Into this the sections may be thrown and allowed to remain until completely saturated with colour, or until they are opaque: they may remain in the staining-fluid from one hour toa day ; but two or three hours is a sufficient length of time. When removed from the staining-fluid they are too deeply stained to be mounted at once, and must therefore be transterred to 95- per-cent. or absolute alcohol, and stirred about in it until the safranin red is no longer given off in clouds from the sections ; but it is important to note that if the sections remain in the strong alcohol too long the whole of the safranin will be washed out. In order to prevent this, when it is seen that the sec- tion has acquired a rosy red hue, combined with a bluish-green tint in the parts stained by the methyl green, the object should at once be removed from the alcohol, thrown into oil of cloves and mounted in balsam or damar. The extraction of the superfluous colour requires from five to fifteen minutes, accord- ing to the thickness and character of thesection, and should on no account be allowed to proceed too far; if it does, the peculiar and important staining-effect of the safranin is lost. As first poited out by Flemming, it has the peculiar property of stainmg the nucleus and its contents while it may be totally removed from other parts of the cell; in fact, as in the oyster-egg, it may be entirely removed from the nucleus and left only in a part of the nucleolus. The methyl green, on the other hand, does not tend to stain the eggs, but rather the spermatozoa and the cells from which they are derived ; and it is one of the most astounding facts known to histological * These are both aniline colours; the first is hard to obtain, except from dealers in dyers’ colours. 40 Mr. J. A. Ryder on the Mieroscopic chemistry, that although both of these dyes, to begin with, are intimately mixed together in the staining-fluid, the diffe- rent histological elements of the section exert some. kind of selective power by which they absorb and hold mainly the one colour only. This peculiar property of the two colours, even when mixed together, enables one to distinctly map out the relations of the sexual elements in the reproductive fol- licles, the nuclei of the ovarian ova being stained red by the safranin, and the heads of the spermatozoa bluish green by the methyl green. The foregoing is mainly the method to which I have had recourse in working out the sexual charac- teristics of Ostrea edulis. Simpler staining-methods suffice in the case of Ostrea virginica and Ostrea angulata. A single colour used in staining sections of O. edulis is lable to lead to error, in consequence of the peculiar mode in which the spermatozoa are packed together in oblong clusters, which are often of about the size of the ovarian ova. This egg-like appearance of the masses of unripe spermatozoa in the fol- licles of the reproductive organs of the common oyster of Europe misled me when examining sections stained only with eosin or carmine. ‘The monochromatic effect produced by one colour only gave no hint as to the real relations of ova and spermatozoa in the follicles until high powers were used with special manipulation of the light. The characteristics of the reproductive organs of Ostrea edulis, O. virginica, and O. angulata are sufficiently marked to be very precisely described and figured, so as to enable any person to appreciate the differences, especially between the first and the last two. O. edulis is essentially hermaphroditic in the structure of its reproductive organs, while the other two are as distinctly moncecious or unisexual. A marked diffe- rence is also to be noted in the relative size or calibre of the reproductive follicles in the hermaphroditic and in the uni- sexual species. In O. edulis the calibre of the generative tubules appears to be relatively much greater than in O. vwir- ginica and O. angulata, nor are the tubules so densely crowded together as in the latter species. Up to this time this difference appears to me to be so marked that I think it would be possible to distinguish sections of O. edulis from those of the other two species by means of this one character. In other respects the history of the development of the repro- ductive tissues in both species appears to be similar. In all, the sexual tissue arises as a linear interstitial differentia- tion between the coarse connective-tissue cells of the animal, only that in O. edulis the rudimentary network does not form quite so close a meshwork as in the other two forms here Sexual Characteristics of Oysters. 41 considered. ‘The tubules have a more extensive anastomiosis with each other in the unisexual species than in the herma- phroditic. In all the forms fine vessels pass off from the dorsal and ventral somatic arteries, which tend to branch into vessels of a capillary fineness amongst the reproductive follicles. Thus the glandular portions of the reproductive organs are effectively nourished by supplies of blood passing from the great vessels given off by the heart. ‘These are the principal characteristic features of the reproductive follicles in the her- maphroditic and unisexual forms which are noticed upon com- paring the two together. The most important differences between the two forms are to be found, however, in the mode in which the generative elements are produced in each type, which we will now consider. In O. edulis the reproductive glands, when well developed, show in many cases a lining of large nearly mature ovules or ovarian eggs at intervals ; and insinuated between them large coarsely granular bodies may be observed, in which large irregular nuclear bodies are often imbedded. These nuclear bodies are further distinguished from those of the ovules by their oval or oblong and often irregular form, and by con- taining a dense mass of granules which absorb safranin in such quantity as to become opaque. ‘This granular chro- matin, as it would be designated by Flemming, is usually ageregated at the centre of the nuclear or cellular mass, which- ever it may be, and is furthermore apt to conform to a certain extent to the external outline of the body which contains it. From these bodies the rounded granular cells appear to arise which fall into the cavity of the tubule or follicle, there to undergo further segmentation, and finally break up into sper- matozoa with spherical heads and filiform tails or flagella. Even (in some cases) where no spermatozoa are as yet re- vealed by the methyl green, these rounded spermogens or spermatoblasts are to be seen free in the centre of the follicles. Usually, however, the spermatoblasts have been crowded towards the external end of the tubule, where they have undergone differentiation into spermatozoa. ‘The sperma- tozoa are often on this account so crowded together at the outlet of the tubules, passing even into the superficial ducts, that when acted on by the methyl green they are revealed as a dense almost opaque dark bluish-green mass. The ovules, on the other hand, which may be quite nearly mature, remain unstained, except their spherical clear nucleus and nucleolus, which ig double, as if formed of two conjoined spherules. If the safranin has been washed out of the nucleus, the one spherule ef the nucleolus only is apt to retain the colour. The 42 Mr. J. A. Ryder on the Microscopic peculiar nucleus of the ovules at once distinguishes them from the elements which later break up and become the sperma- tozoa. Apparently every phase of the spermatogenetic pro- cess is under way in the follicles, while more or less nearly mature ovules may be adherent to the walls of the same tubules. In some specimens I find the tubules to contain nothing but ova, with little or no trace of spermatoblasts; in others, again, both classes of products may be present in about the same condition of maturity. In still others little else but spermatozoa are to be found, but, adherent to the walls of the follicles, cells are to be found which have the nucleus so characteristic of the more mature ovules. These, I am in- clined to believe, are the representatives of what will later become ova, and not the representatives of spermatoblasts. It is a singular fact that the spermatozoa have a tendency in O. edulis to cling together in masses of about a uniform size. Though the spermatic particles which compose these masses are somewhat separated from each other, 1f compressed to- gether they would evidently form a body about the size of the spermatoblasts from which they were derived. Later they tend to break up and form a more homogeneous granular mass at the outlet of their parent tubule, where the latter joins the outgoing efferent duct. While it is true that some sections of O. edulis show little evidence of the presence of any thing else but the product of one sex, it appears to me that there is suffi- cient evidence of the hermaphrodite character of the genera- tive glands of the species presented by a pretty large series of sections taken from about fifty individuals from different localities along the coasts of Wales, Scotland, England, France, Holland, and Germany. Sometimes a portion only of a section will be hermaphroditic, showing that different parts of the generative glands of the same animals may be of different sexes. The result of this arrangement is that it is scarcely possible for the eggs to escape impregnation by the milt generated alongside of them, and we may, I believe, fairly assume that Ostrea edulis is a selt-fertilizing herma- phrodite. The condition of things in the generative tubules of Ostrea virginica and angulata is very different, as may be gathered from the following account. In the first place I have never found any evidence of hermaphroditism either in the living animal or in sections of the reproductive organs. The mode of pressing out the spawn from the gland and ducts of O. vir- genica, and the physical test used to determine the sex of the products in practical work during the last season, afford the most positive demonstrations of the unisexuality of that species. Sexual Characteristics of Oysters. 43 Examining sections, however, we never find either in the reproductive follicles of O. virginica or of O. angulata any evidence of the coexistence of ovules and spermatozoa. In fact the mode of spermatogenesis in the unisexual species is very different from that of the hermaphroditic. As indicated in Brooks’s figure of a part of a section of a male oyster, the spermatozoa are peculiarly arranged in the follicle or tubule. Upon applying a high power (500 to 800 diameters) I find that the heads of the spermatozoa show a very marked tendency to be arranged in rows like beads, and not in oblong clusters as in the hermaphroditic species. Moreover the walls of the generative tubules are lined by relatively very much smaller spermatoblasts than those found free in the repro- ductive follicles of the hermaphrodite form. ‘This spermato- genetic layer is often very marked in the males of the uni- sexual species, and even at an early stage of the functional activity of the testicular organ presents much the same struc- ture that it does later. ‘The rows of spermatozoa already alluded to also have a tendency to be bent towards the outlet ot the tubules, giving rise to a fringe-like appearance on either side of the follicle with a clearer space between the edges of the fringe-like masses of spermatozoa. In fact it is plainly to be seen that the spermatozoa are being budded off from the spermatogenetic layer, and that the appearances just described are a result of that process. It results from this that the structural peculiarities of the testicular tubules are very cha- racteristic, so that once recognized they will never afterwards be confounded with the arrangement observed in the ovary of the female, where, as in the hermaphrodite species, the ova may be seen in different stages of development, though, where the majority of the ovules have attained nearly full develop- ment, it may happen that few of the nascent ovules closely adherent to the walls of the follicles are visible. The distinction between Ostrea edulis and the American and Portuguese species is therefore very marked and impor- tant. Mdébius(‘Die Auster unddie Austernwirthschaft,’ Berlin, 1877, p. 19) says of their species: —Oysters are hermaphro- dites. In the largest number of individuals, in the whole repro- ductive organ | found only spermatozoa, but no eggs. In seven oysters which carried blue brood in the beard, the sexual gland contained only spermatozoa. Three oysters with younger white embryos in the beard had no spermatozoa in the sexual gland. Inthe most of the brood-bearing oysters the sexual gland contained neither eggs nor spermatozoa. Of 309 oysters which were taken on the 25th of May from four different banks east of the island of Sylt, and afterward examined 44 Mr. J. A. Ryder on the Microscopic from May 26 to June 1, 18 per cent. were hermaphroditic, and of the remaining 82 per cent. one half were egg-bearing, the other half sperm-bearing. In none were the sexual pro- ducts completely mature. From these observations I con- clude that the eggs and spermatozoa do not develop simulta- neously but successively in the sexual gland; that sperma- tozoa may be developed very soon after the discharge of the ova, and that probably one half of the oysters of one locality during a breeding-period produce only eggs and the other half produce only spermatozoa.” To the same effect are the statements of Lacaze-Duthiers ; but Davaine seems to have first noticed the peculiar aggregations of spermatozoa in oval masses in Ostrea edulis. Brooks thinks “ Gerbe’s statement, that among the 435 European oysters one year old he found 35 with young, 127 with ripe eggs, and 189 with ripe semen, seems to be sufficient to show the incorrectness of Lacaze- Duthiers’s conjecture that the functionally male condition precedes the functionally female condition.” This is about the state of the controversy at present in re- gard to the breeding-habits of Ostrea edulis. ‘The only authority, as far as 1 am aware, who distinctly takes the ground that eggs of this species are fertilized in the repro- ductive organs is Horst, who says, “‘ Not only do the embryos pass through their first stages of development within the mantle-cavity of the adult, and impregnation occurs internally instead of externally, but it may also be said that the eggs and spermatozoa come into contact in their passage out of the generative glands.” It is barely possible, indeed probable, if my memory serves me rightly, that Davaine has put similar observations upon record. Horst also distinctly asserts that the normal development of the embryos of Ostrea edulis cannot take place outside of the parent. M. Berthelot, according to Mr. Brandely, has discovered that the fluids in the mantle- cavity of O. edulis contain albumen in a notable proportion, upon which the young are supposed to be nourished. Mr. Brandely has found, by direct experiment, that in the case of QO. angulata it is possible to artificially impregnate the eggs. His attempts to fertilize the eggs of O. edulis with the milt of O. angulata and vice versa were unsuccessfully repeated at different tires for the last two years. I am now also uncer- tain in regard to the identity of the species of which Lieut. Winslow succeeded in artificially impregnating the eggs at the mouth of the St. Mary’s River, in the Bay of Cadiz, Spain, which he says were natives, the variety having existed and flourished in the bay for as far back as could be remembered, I quote his description of the specimens he used in his experi- Sexual Characteristics of Oysters. 45 ments as follows :—“ In appearance they were quite similar to the American species (Ostrea virginica), having long shells of from 1 to 3 inches in length, rougher and thicker than is usually the case with the Huropean oyster.’ This remark raises the question whether the experimenter was not really working with O. angulata instead of O. edulis. The locality where he got his specimens and where he conducted his expe- riments also makes it not improbable that he was in reality working with the native unisexual species, O. angulata. To return to the question of the breeding-habits of Osérea edulis, it appears to me that we cannot very well question the authority of Mobius, Lacaze-Duthiers, and Horst, in regard to the bisexual state of the reproductive organs. My investiga- tions also give some countenance to the fact of a preponderance either of eggs or of spermatozoa in different individuals ; in fact, in some cases the one or the other seems to be almost exclusively the mature product. But we are not yet in a position to arrive at a conclusion in this matter, because of the scantiness of the observations which have hitherto been made. The hypothesis that the spermatozoa are drawn from without into the generative ducts by the ciliary action of the gills and mantle may be dismissed with the remark that microscopic investigation, to my mind, has effectually disposed of the pro- bability of any such a state of affairs. We may see the sper- matozoa in course of development in the same follicle with the ova, which is conclusive proof that the milt has not been de- rived from without, from the water into which it had been discharged by neighbouring individuals. In truth, we find in some cases the spermatozoa present so deep down in the utmost ramifications of the generative follicles that it is not conceivable that they should have been drawn in from without. As to the alternate activity of the organs in producing ova and spermatozoa, there is a possibility that such is the case, but, as stated at the outset, there is as yet no conclusive proof of the fact. Certain it is that I have yet to see sections of O. edulis in which both ova and spermatozoa are not present in some condition of development at the same time. If the one be not present in a fully developed state, developing traces of it may be discovered; or even a very minute quantity of developed milt or a few developed eggs may be present in some one follicle, while in the others there are perhaps exclu- sively eggs or exclusively milt in a developed condition. I am aware that this view of the matter is opposed to the current doctrine that nature provides against continuous inter- breeding ; but when we find the eggs and milt about equally 46 Mr. J. A. Ryder on the Microscopic advanced in development in the same follicle, what is there to prevent self-fertilization ; in fact, what else can be the mode of reproduction ? In some of the sections of O. edulis examined by me, the ovules already measured 34, of an inch in diameter, showing them to be about twice the size of the ripe eggs of O. virginica and O. angulata, in both of which the ova are of about the same size when mature. Estimates which I have made, based on the figures of the eggs of O. edulis given by M. Davaine, show them to bez) of aninch in diameter. Estimates based on the figures of Lacaze-Duthiers give 3}; of an inch, while Mdbius and Horst give the size of the young fry at 74, of an inch in diameter. ‘The spherical heads of the spermatozoa of the three species here discussed measure about the same, or approximately y455 of an inch in diameter. The clusters of spermatozoa of O. edulis measure approximately 755 of an inch in diameter. ‘he spherical unsegmented spermatoblasts which break up into spermatozoa in QO. edulis measure jsp Of an inch in diameter. The nucleus of the ovarian eggs of O. edulis measures not quite 45 of an inch in diameter. The nucleus of the ovarian egg of O. anguluta measures approxi- mately y';; of an inch in diameter, which is about that of the nucleus of the egg of O. virginica. The large spherule of the nucleolus ot the egg of O. edulis measures sisy of an inch in diameter; the small spherale, which is stained red by the safranin, measures z3';5 of an inch; the long diameter of the conjoined spherules is 7757 of an inch. The long diameter of the nucleolus of the egg of O. angulata and QO. virginica is about zol5y Of an inch. A slide in my possession containing some of the brood of O. edulis shows that, even after it has acquired both vaives of the shell within the beard of the mother oyster, the brood varies greatly in size. I find, for example, that such fry measures from >} > of an inch down to as smallas ;4;5. This brood, like that of the American oyster, has not yet acquired any umbonal promi- nences at the hinge end of the valves. Before this occurs in the American-oyster embryo considerable growth has taken place ; but when the shell already covers the body the whoie embryo, contrary to what is found in the European species, measures little, if any, more in diameter than the egg, or about s4> of an inch. Later, when the embryo has grown considerably, and when it is on the eve of attaching itself permanently, it measures from 345 down to yo of an inch in diameter. The mode of fixation of the fry of both species is probably the same ; but the mode of incubation (the one in the mother, the other in the open water), we see, is widely diffe- Sexual Characteristics of Oysters. 47 rent, differing as greatly in this respect as do the eggs in size and details of construction, as shown by the measurements which I have given. It must not be forgotten, however, that the material from which I prepared my sections was received from Europe in January and March, when it is to be supposed that the reproductive organs were not yet fully developed, and that consequently the dimensions of the ovarian ova as found by me are rather to be considered as being below than above their true ones when fully developed at the height of the spawning-season. It is a very remarkable fact that one finds individual speci- mens of oysters in which the reproductive organs have under- gone total atrophy or wasting-away at the completion of the spawning-season. Hxamining sections through the body-mass of spawn-spent oysters taken from their native waters in August last, I find that the whole of the connective tissue subjacent to the mantle, and between the latter and the liver, especially over the sides of the body-mass, has disappeared, together with all traces of the reproductive organs, including the superticial branches of the efferent ducts. At the first bend of the intestine there is still some of the connective tissue remaining; but even here and in the mantle it has changed its character entirely, and become very spongy and areolar, instead of solid and composed of large vesicular cells such as are met with when the animal is in a better condition of flesh. In fact, it appears as if this mesenchymal or connective-tissue substance had been used up and converted into reproductive bodies (generative products) in the case of the spawn-spent and extremely emaciated individuals. In sections of indivi- duals in various conditions from that in which the rudimentary netwcrk of generative tubules has just appeared in the con- nective tissue, on up to those in which the reproductive tissues are enormously developed in bulk and proportion to the mass of the remaining structures, there is a perfect gradation from their complete absence to their full development. This would appear to be very strong evidence in support of the theory that the reproductive follicles, or tubules, are developed anew each season directly from the specialization of certain strings or strands of connective-tissue cells. Many animals manifest a periodic development of the glan- dular portions of the reproductive organs; but I know of no form in which there is any such presumptive evidence that these organs are annually regenerated and finally altogether aborted as seems to be the case with the oyster. ‘Together with the changes here described, the most remarkable changes in the solidity and consistence of the animal take place. The 48 Mr. A. Haly on Rhinodon typicus. shrinkage of a spawn-spent oyster in alcohol or chro mic-acid solution is excessive, and will, when complete, reduce the animal to one tenth of its bulk while alive. This shrinkage is due to abstraction of the water with which the loose spongy tissue of the exhausted animal is distended. A so-called “ fat” oyster, on the other hand, will suffer no such excessive dimi- nution in bulk when placed in alcohol or other hardening fluid. In consequence of this variable development of the reproduc- tive organs as well as that of the connective tissue of the body-mass, the amount of solid protoplasmic material con- tained in the same animal at different times under different conditions must vary between wide limits. And inasmuch as the nutritive and reproductive functions of animals are notoriously interdependent, it follows, in consequence of the enormous fertility of the oyster, that a vast amount of stored material in the shape of connective tissue must be annually converted into germs and annually replaced by nutritive pro- cesses. Plentitude or dearth of food are also to be considered; but it now becomes a little easier to understand the physiolo- gical interdependence of the reproductive function and the so-called fattening process. To a great extent what has been remarked in the preceding paragraphs of the wasting-away of the reproductive organs in Ostrea virginica seems to apply also to O. edulis and O. angulata. The last species has an extraordinarily thick body- mass, with the stratum of reproductive follicles of remarkable thickness, averaging a much greater development than I have ever seen in any other form. When the contents of this great mass of tubules has been discharged a diminution in the bulk of the body-mass must naturally ensue, probably accompanied by a wasting-away of the connective tissue and tubules, such as apparently occurs in the American species. From what I have seen of the generative tubules of QO. edulis in sections, they are evidently regenerated much as in O. virginica. In a few specimens: I find them almost entirely gone, or present only in an extremely rudimentary state. VI.— Occurrence of Rhinodon typicus, Smith, on the West Coast of Ceylon. By A. HAty. On January 5th a large female shark which I identify as Rhinodon typicus was entangled in the nets at a fishing- village called Moratuwa, twelve miles south of Colombo. The native population were greatly excited, and flocked in large Mr. A. Haly on Rhinodon typicus. 49 numbers to the beach to see it, fish of this size being very rarely caught on this coast. The following are the principal measurements :— Total length from point of upper jaw to tipof ft. in. HIB PERC AMC TOME) 0). %) salle! Wy: 0's» «i $e eccreeeee 23 9 Gurihi-hebimd pectoral, fo. asa «ays; ale. aie! ss) cal Aen 13 0 Distance of first dorsal from point of upper jaw 10 0 AMeTION CASS OF ATTEO Wie see wes os nee 110 BSevORtECONe IPA k ORES 1 10 Distance between first and second dorsal .... 2 8 Pmerioredee Of GUtO asatie'ee's se a oo ieee aes 0 11 raed CEECUBLON at waar. Sata e wine wuin ase craic iss 0 11 Length of upper caudal lobe .............. 5 0 Length of lower caudal lobe ....¥......... th Anterior edge\ofianall s./. o.i54\4 Dae cae os eh 0 9 PSO OG NGL Ole ct ayers che tbe esis wepey annie aps tefees fetete 0 9 AMLTIOL Cd26, OF VENENAD yao. yasy sss 03/05 Ey Ere Ses GIMUUDOl nyc se scc/Sisistee +4 4610 wars se ape. c'est Let Anterior edge of pectorals shes. ee eek 3.6 Depth of second gill-opening ............., 2017, Diamacter, ef spiracles sii. a a64 iis a6 viel e's g'erqievern s 0 13 WD ihiO1 OF Ci Cranes 1 tal ores outer siete. « Shaye “Paid view jewels 0 12 The width of the mouth when fresh was 3 feet ; but it has shrunk in drying to 1 ft. 1lin. The form of the mouth is lost in the mounted specimen. When fresh the lower jaw was quite straight and flat, nearly, if not quite, on a level with the surface of the abdomen, and considerably in advance of the upper, so that the band of teeth in the lower jaw was quite uncovered. This band averages 1 inch in breadth, and con- sists of fourteen rows of minute, sharp, recurved teeth, 2 millim. long, all of equal size. The band in the upper jaw is ? inch broad, and consists of eleven rows of similar teeth. I was in hopes of finding either eggs or embryos, which are occa- sionally to be obtained from large sharks and skates caught at this season ; but there was no sign of her having approached the shore on account of its being the breeding-season. The stomach contained a quantity of finely divided red matter. This makes the sixth species, obtained mostly near Colombo,’ not mentioned in Day’s ‘ Fishes of British India,’ and now in the collection of the Colombo Museum. They are :— Branchiostoma lanceolatum, Pall. Rhinodon typicus, Smith. Diodon maculatus, Giinth. Chilinus undulatus, Riipp. Xiphochilus robustus, Giinth. Peristethus ? Near Galle, deep water, probably about 50 fathoms. Ann, & Mag. N. Hist. Ser. 5. Vol. xii. 4 50 Mr. A. G. Butler on Formosan Lepidoptera. VII.—On a Third Collection of Lepidoptera made by Mr. H. E. Hobson in Formosa. By ArtuurG. BUTLER, F.L.S., F.Z.8., &e. Towarps the end of last year I received a small box of Lepidoptera in envelopes from Mr. Hobson accompanied by a letter, of which the following is an extract :— “ Tamsiu, September 6, 1883. “ Dear Mr. Burter,—Having just been transferred from this to the north, I am sending you what moths &c. I have annexed since arrival. “T had an opportunity of visiting the south cape of the island early in the spring, and obtained the large butterflies down there. The moths are all from this end.” The collection contained some well-known species pre- viously received, and which Mr. Hobson requested me to forward to the Derby Museum ; these species therefore are not included in the present list. One of the most interesting additions to the fauna in the present consignment is Hestia clara, three examples of which (“ihe large butterflies ’?) were obtained in the south ; an ex- ample of Ornithoptera rhadamanthus was probably taken at the same time. The following is a list of the butterflies. RHOPALOCERA. 1. Hestia clara. Hestia clara, Butler, Trans, Ent. Soc. ser. 3, vol. v. p. 469. n. 6 (1867). South Cape. The type of this species was supposed to be from Java. 2. Parantica aglea. Papilio aglea, Cramer, Pap. Exot. iv, pl. 877. E (1782). S. Formosa. 3. Ypthima multistriata, n. sp. Allied to Y. nareda and Y. corticaria, intermediate in size between the two. Wings above smoky brown, paler on the disk of the wings, especially in the female, and with blackish Mr. A. G. Butler on Yormosan Lepidoptera. 51 submarginal and marginal stripes: primaries of the female with a large oval bipupillated ocellus towards the apex, the male rarely showing a trace of a similar ocellus, but usually entirely destitute of it: secondaries with a large circular uni- pupillated ocellus on the first median interspace, and fre- quently, in the male, one or even two minute subanal ocelli in an oblique line with the large ocellus: primaries of the male with a blackish nebula over the median area. Under surface sordid white, the primaries and base of secondaries more or less suffused with brown, and the entire surface of all the wings densely covered with numerous sharply defined darker brown strie; marginal and submarginal stripes as above: primaries in both sexes with a well-defined bipupillated black subapical ocellus with pale yellow iris ; a dark brown stripe from just beyond the middle of the costa across the disk to the ter- mination of the submarginal stripe: secondaries crossed beyond the middle by an irregularly angulated stripe, some- times barely traceable, but usually well defined; three well- defined ocelli, one apical and two subanal, the last being smaller than the others and bipupillated. Expanse of wings 37-42 millim. Seven examples, N. Formosa. The specimens of this species are for the most part more or less shattered, as though they had been long on the wing. 4. Calysisme mineus. Papilio mineus, Linneeus, Syst. Nat. i. 2, p. 768, n. 126 (1766). N. Formosa. 5. Cyaniris puspa. Polyommatus puspa, Horsfield, Cat. Lep. E.1. Co. p, 67. n. 3 (1828). A worn female, N. Formosa. 6. Nychitona niobe. Pontia niobe, Wallace, P. Z. 8. 1866, p. 357. n. 6. N. Formosa. One example has the apical spot better developed than usual, so that it looks like a pale specimen of P. xiphia. 7. Terias unduligera. Terias unduligera, Butler, P. Z. 8. 1880, p. 668. n. 22. N. Formosa. The external border of the secondaries appears to vary in width, as in the two males now received it is as wide as in At 52 Dr. Wallich on Polycystina tn certain Nodular Flints. T. hecabe; they may, however, be hybrids between the two species. 8. Tertas hecabe. - Papilio hecabe, Linneus, Mus. Lud. Ulr. p. 249 (1764). N. Formosa. 9, Ganoris glictria. Papilio gliciria, Cramer, Pap. Exot. ii. pl. 171. E, F (1779). 9. N. Formosa. 10. Ornithoptera rhadamanthus. Ornithoptera rhadamanthus, Boisduval, Sp. Gén. Lép. i. p. 180. n. 8 (1836). 2. 8S. Formosa, Owing to press of work it has been necessary to defer giving an account of the moths in this collection. VIIL—wNote on the Detection of Polycystina within the hermetically closed Cavities of certain Nodular Flints. By Surgeon-Major Wauiicn, M.D. In continuation of my previous papers on the “ Origin and Mode of Formation ot the Cretaceous Flints’”*, I beg to an- nounce the discovery by me, last summer, of a number of well-marked Polycystina amongst the loose fossilized contents of nodular flints obtained from the Surrey gravel-pits. In common with other observers I have often noticed minute objects in flint sections, which are, in all probability, the re- mains of these organisms; but in no instance were the appearances revealed by the microscope sufliciently distinct to place their identity beyond question. In the case of the structures now under notice there can be no doubt of the kind; and we are thus furnished with another interesting link in the chain of evidence which goes to prove the general lithological identity of the chalk with recent deep-sea calca- reous deposits. The genera of Polycystina met with in the nodular cavi- ties are, for the most part, Astromma, Haliomma (both dis- * Quart. Journ. Geol. Soc. for Feb. 1880, and Ann. & Mag. Nat. Hist. for Feb., March, and July 1881. Mr. J. Wood-Mason on Scolopendrella. 53 coidal and spherical), and Podocyrt’s. A few specimens of well-marked fossilized Dictyochide also occur. Both the Polycystina and the Dictyochide, as well as the mass of the loose granular material associated with them in the same flint- cavities, are more or less metamorphosed by a slight admixture of peroxide of iron and calcite, the former substance having imparted to the entire structures a bright reddish hue. Through the courtesy of Prof. T. G. Bonney, F.R.S., I have been enabled to examine a slide of ‘ diaspro ” contain- ing Polycystina. These, however, exhibit somewhat less of the characteristic structure of the organisms, owing, no doubt, to their having become fossilized under less favourable conditions than those which existed in the hermetically closed flint-cavities. In both cases the polariscope shows the silica to have been partially replaced by calcite. I have likewise found in material obtained from hermetically closed flint-cavities, by far the most perfectly preserved Fora- minifera I have ever seen, the shell-structure and chambers, with every minutest detail of tubular structure, having been converted into chaleedony—the whole mass by reflected light presenting a beautifully whitish-blue opalescent appearance, whilst by transmitted light it exhibits a rich transparent burnt- sienna colour and the well-known fibrous character of chalce- dony wherever that substance is most massive, as, for instance, within the chambers. The Foraminifera represented belong chiefly to the genera Rotalia, Globigerina,and Textularia. I may add that, as regards perfection in every minutest detail of shell-structure, these specimens greatly surpass in beauty those metamorphosed into glauconite, beautiful as they also un- doubtedly are. 1X.—Notes on the Structure, Postembryonic Development, and Systematic Position of Scolopendrella. By J. Woop- Mason, Deputy Superintendent, Indian Museum, Calcutta. THIS interesting and remarkable type of Tracheate Arthro- poda was first made known to science in 1839 *, in which year the distinguished zoologist Prof. P. Gervais brought to the notice of the Academy of Sciences at Paris some speci- mens of a small and fragile Myriopod which had been disco- vered in the vicinity of the French capital; and founded * ¢ Comptes Rendus,’ tome ix, p. 582 (1839). 54 Mr. J. Wood-Mason on Scolopendrella. upon them the genus Scolopendrella. This preliminary notice was followed in 1844* by a description with figures of the species under the name of S. notacantha, which description and figures were in 1847 f repeated in the ‘Suites a Buffon.’ A second species was not long afterwards described and figured, from specimens obtained near London, by our own countryman Newport }, who at first thought the genus allied to the Chilopodous Geophilus, but eventually placed it in a family by itself between Lithobius and Scolopendra, notwith- standing that the fourth somite and its appendages are not developed into the basilar plate and poison-claws so charac- teristic of Chilopoda. In 1851 a memoir §, which is far the most complete of any that have as yet appeared, was published by Menge on New- port’s species S. ¢mmaculata. This author, who discovered the silk-glands that lie in the last two somites and open at the ends of the caudal appendages, as well as the trachee (which he did not, however, correctly interpret), and several other structural features of importance, regarded the genus Scolopen- drella as “ the type of a genus or family intermediate between the hexapod Lepismide and the Scolopendride ;” but he re- frained from making a new name. Lubbock ||, Huxley §, and others have briefly referred to the genus. I myself in 1876 ** recorded its occurrence in Bengal, and in 1879 {} published a few observations upon it and figured one of the legs. In 1880 {{ Mr. J. A. Ryder recognized in it “ the last sur- vival of the form from which insects may be supposed to have descended,” and proposed for its reception ‘the new ordinal group Symphyla, in reference to the singular combination of Myriapodous, Insectean, and Thysanurous characters which it presents ;” and in 1881 the same writer monographed the * Ann. d. Se. nat. Zool. tom, ii. 1844, p. 70, pl. v. figs. 15-17. + Walckenaer et Gervais, Ins. Aptéres, t. iv. pp. 301-3803 (1847). ¢ Trans. Linn. Soc. Lond. vol. xix. pp. 373, 374, pl. xl. figs. 4, 4a, b, c; and Cat. Myr. Brit. Mus. § “Myriapoden d. Umgegend y. Dantzig,” in Neueste Schr. d. natur- forsch. Gesellsch. in Danzig, iv. 4tes Heft. || ‘Monograph of Collembola and Thysanura.’ € ‘Anatomy of Invertebrated Animals.’ ** Proc. Asiat. Soc. Bengal, August 1876. ++ “Morphological Notes bearing on the Origin of Insects,” in Trans. Ent. Soc. Lond. 1879, p. 158, fig. 2, B. tt Amer. Nat. May 1880. The number of this publication for Septem- ber of the same year contains a note on Ryder’s communication, with some figures and suggestive remarks on S, emmaculata. ————— Mr. J. Wood-Mason on Scolopendrella. 55 group*, describing a new species, and giving a useful sum- mary of Menge’s important paper. In 1881 } there appeared a paper by Dr. Jos. Muhr which is said to contain a valuable description of the mouth-parts of a new species closely allied to S. notacantha, but which I have not yet seen. Finally, in the present year Dr. 8. H. Scudder, of Cam- bridge, Mass., U. 8S. A., described a new species under the name of S. latipes. I have arrived at the conclusion that Scolopendrella is a Myriopod which, while resembling the Chilopoda in the form of the body, is more nearly related to the Chilognatha; but whether it should be classed as a suborder of the latter or in an order by itself we shall be better able to say when we shall have learnt more about its anatomy and development than we at present know. And I regard it as the descendant of a group of Myriopods from which the Campodee, Thysanura, and Collembola may have sprung, looking upon the three latter groups as the living representatives of the extinct stock or stocks from which the various orders of insects have origi- dnate,—the jointed (Myriopodous) mandibles and the presence of two pairs of appendages (the one a pair of walking-legs and the other a pair of styliform rudiments) on each of the two hinder thoracic somites, and of two pairs of rudimentary feet on each of two of the abdominal somites, in Machilis seeming to me explicable only on the hypothesis that this form is de- scended from an animal allied to the Chilognatha, and the somites of whose body were provided with two sterna, each furnished with a pair of appendages of the value of legs; and the resemblances of the true insects through Blatta to the Entomopsida (Campodez, Thysanura, and Collembola), on the hypothesis that the two have a common ancestry. Seeing that there occur in combination in Scolopendrella two of the most remarkable features of Peripatus, namely two- clawed feet and segmental openings, its ancestry may be in- ferred to have lived and flourished before the present types of Myriopoda were evolved ; and it may therefore throw much light on the origin of Myriopods also: it may, for example, atford an explanation of both the modes of addition of fresh segments—that which “ takes place by the way of intercala- tion at each moult in the intervals between each pair of older segments,’ and that by their interposition between the penul- * Proc. Acad. Nat. Sci, Phil. 1881, pp. 79-86. T Zool. Anz, iv. 1881, pp. 59-61, figs. 1, 2, and 4. 56 Mr. J. Wood-Mason on Scolopendrella. timate and antepenultimate somites—which obtain in Chilo- poda, and of the nature of the double somites in Chilognatha. The Head.—This is not so depressed as it is represented to be in the published figures, but is anteriorly deflexed, with the antenn articulated to the forehead, much as in the Chilogna- thous Myriopoda. Its anterior margin is divided by a median notch into two rounded, thickened, and highly indurated lobes, each armed at the extremity with three sharp spiniform processes supported by buttress-like thickenings and directed with their fellows of the opposite side towards the middle line, thus recalling the sharp and toothed rostrum of Chilo- enatha. On the upper surface of the head, behind the insertion of the antenne, and in the same transverse line as the mandibular articulations, lie a pair of smooth and slightly convex arez with an exceedingly sharply defined and doubly contoured oval outline; they appear to be cake-shaped involutions of the integument; and their walls are covered with a minute punc- tuation, which may possibly be the optical expression of the ends of fine canals. If a spirit-specimen of the animal be placed whole in a solution of hematoxylin for a few hours, these organs become filled, or their contents deeply coloured, by the reagent; so that they must freely communicate with the exterior. Whether they are glands, or stigmata, or eyes, can only be decided by means of sections; 11 would be worth while to compare them with the paired organs externally visible in the corresponding part of the head in Glomeris as conspicuous horseshoe-shaped impressions. Between these structures and the insertion of the antenne I have not yet succeeded in making out the “ round black eyes” which have been described by Menge; and it is possible that the two may be the same. Previous observers have all recognized two pairs of jaws in addition to the mandibles, namely a pair of first maxille and a pair of second maxille, equivalent to the so-called labium of insects, but no other cephalic appendages ; and they all appear to me to have misdescribed those that they have recognized, I, on the contrary, see in the supposed two pairs of gna- thites that succeed the mandibles but the coalesced parts of a single pair, resembling in all essential particulars the four- lobed plate that follows the mandibles and functions as a lower lip in the Chilognatha; and I have no doubt that the first pair of legs is the third pair of postoral appendages an- swering to the labium of insects. First Pair of Postoral Appendages.—In specimens mounted Mr. J. Wood-Mason on Scolopendrella. 57 in spirits, with the dorsal surface upwards the mandibles are visible beyond the sides of the head, between the oval sacs above described and the insertion of the antenne. They are therefore attached very far forwards ; and their strong articu- lation is rendered very conspicuous by the amber-like colour of the cuticle, both of their posterior extremity and of the part of the head into which this fits—amber-like coloration indi- cating the great firmness of the chitinization that has taken place. They are divided by a very distinct joint, visible just in front of the insertion of the antenne, into two segments: the first of these is a slightly curved prism attached to the head by its dorsal margin, and to the outer lobe of the four- lobed plate by its ventral margin, its inner side being conse- quently open, so as to give passage to the flexor muscles, which are inserted into the inner face of its outer wall; the second, a triangular plate, is armed on its inner side with two distinct series of teeth distinctly separated from one another by a rounded notch, the posterior series consisting of five small equal pale and blunt tubercular ones, and the anterior of four dark brown and highly indurated sharp teeth, of which the anterior and outer is slightly the largest, and lies in a different plane from the rest; from the bottom of the notch between the two series of teeth a faint groove encircles the joint, subdividing it into two, corresponding respectively to the first (which in Glomerds is developed on the inner side into an antero-posteriorly elongated molar process) and second or apical (which is bifureate*) free joints in Chilognatha gene- rally. ‘The mandibles can be readily disarticulated from the head, as also can their two principal joits from one another. They are, in short, built exactly upon the plan of those of the Chilognatha, being divided into three distinct joints, and therefore not consisting, as has been stated, of a single piece only. Second Pair of Postoral Appendages.—These are made up of seven or eight distinct sclerites, all united together by membrane, namely :—four lateral, of which two are long and * The apical joint in all Chilognatha consists of two parts attached to a common hbase (the first free joint), but lying in different planes and applied to each other, much as are the “galea” and “lacinia” of the first maxillz in such an insect as the common cockroach—an arrangement strongly suggestive of its being, like the jaws of Peripatus, a moditied pair of claws. The objection to this is that all living Myriopods except Scolopendrella have the legs terminated by a single claw; and it would be fatal were it not that the legs of the Protracheata are biunguiculate. The uniunguiculate condition of the legs in most Myriopods, in the larvee of many insects, and in all the Collembola is probably adaptive. 58 Mr. J. Wood-Mason on Scolopendrella. anterior or apical, and two are short and posterior or basal ; two median ; and one or two basal. The two median sclerites are much broader than the long laterals; and they form toge- ther a broadly spatulate figure, which extends quite up to the toothed and lobed anterior margin of the head in front, and behind is divided into two divergent horns embracing the sides of the triangular basal sclerite. The long or apical lateral sclerites are attached not only to the medians and by the basal moiety of their outer margins to the ventral margin of the basal joint of the mandibles, but also by the intermedia- tion of the short laterals to the basal part of the basal sclerite, which may be divided transversely into two parts; and they taper from their base to their apex, which reaches only to the end of the first mandibular joint and carries two large movably articulate appendages. These ordinarily le with their apices all directed towards one another in the middle line, concealed beneath the rounded end of the conjomed median lobes ; but when pressure is put upon the covering-glass they diverge and project straight forward for some distance beyond the front of the head *. They both lie in the same plane; and the outer (which is a highly indurated, slender, straight, and tapering organ, hooked at the extremity and provided inter- nally with a minute anteapical spiniform process) fits the inner (which is a soft finger-shaped body with a brush of apparently implanted bristles on its inner extremity) as the ““oalea” does the “lacinia” in the first maxilla of the cockroach—with which parts of the insectean maxille they can have nothing whatever to do, being plainly homologous with the two short and similarly convergent appendages that are present at the end of each outer lobe of the same pair of jaws in all Chilognatha, and being probably, like these and like the tips of the mandibles, modified pairs of claws inherited from the common Protracheate ancestor. Third Pair of Postoral Appendages.—Of the fifteen dorsal sclerites which in adults follow the head, the first is little more than a mere short and transverse fold of skin with scarcely a trace of the conspicuous imbricating process given off from the posterior margin of all its successors ; it is the tergum of the somite that bears the first pair of legs. These differ from those of the remaiming eleven pairs in being conspicuously smaller and slenderer, with their last joint elongated, and their last but one shortened and apparently confounded with the third, in bemg more approximated at * The fore margin of the median lobe also becomes protruded so as to display the six conical spines with which it is furnished. — 2.0 Mr. J. Wood-Mason on Scolopendrella. 59 their bases (where they are attached to two sinall oval sclerites nearly touching one another in the middle line), but above all in the important circumstance that they are never brought to the ground, but, on the contrary, are turned forwards under the head so as to be quite invisible from above in the living animal ; commonly, indeed, they are folded akimbo across the under surface of the back of the head; they without doubt belong to the head, and they must, as they follow the four- lobed plate, be held to correspond to the similarly pediform and attached appendages of Chilognatha, and, as a conse- quence, to the labium of the Insecta. The Somites of the Body und their Appendages.—The body of this little animal is extremely soft and fragile and exten- sible, and tapers visibly from the fourth leg-bearing somite towards the head, which is but little broader than the tergum of its hindermost somite. It is little, if at all, broader than high ; and the soft membrane intervening on its sides between the leg-bases and the projecting lateral margins of the tergites is complexly puckered and folded in a manner reminding one of the Chilopoda. It is defended above by thirteen (exclusive of the caudal somite, which would appear to be double) imbri- cated plates or terga, whose hinder margin is divided by a pronounced emargination into two rounded lobes. In this series of terga no such regular alternation of longs and shorts as obtains in many Chilopoda is to be observed, nor equality, nor regular decrement or increment, but, on the contrary, a marked irregularity in length—an irregularity, however, which is identically the same in all the specimens hitherto examined. On turning to the ventral surface, a consecutive series of eleven precisely similar regions, to each of which two distinct pairs of appendages are movably articulated, can readily be made out, or two less than the number of the terga opposed to them ; consequently two of these must be without either appendages or sterna, or two of the somites must be considered to be provided with double terga. In each of these sternal regions two pairs of sclerites are discernible :—a posterior pair of nearly circular and smaller ones, which, without doubt, corresponds to the small and similarly shaped ones that carry the hindermost pair of cephalic appendages, and external to which a pair of stout five-jointed and biunguiculate legs are attached ; and an anterior pair of elongated and larger sclerites, near to the postero-lateral margins of which, and between which and the legs, are articulated a pair of short setose styles. This arrangement of the parts at once suggested the sus- picion that each of the regions was made up of two sterna, each marked by a pair of appendages, the anterior and inner of which had become reduced to styliform rudiments—a sus- 60 Mr. J. Wood-Mason on Scolopendrella. picion the correctness of which has been verified by the study of several stages in the postembryonic development of the animal. So that eleven pairs of rudimentary legs and eleven pairs of functional ones, or twenty-two in all, marking as many separate somites, are to be made out in this animal between the head and the tail. The presence of the two apodous terga and of the eleven pairs of rudimentary feet seems intelligible only on the suppo- sition that Scolopendrella has been evolved from a form with twenty-two distinct and complete leg-bearing somites, by the reduction to rudiments of the legs (accompanied by the abor- tion of the metamerically arranged organs, such as stigmata and excretory pouches of the somites), and the suppression of all but two of the terga of alternate somites. The terminal tergum, which is longer than broad, truncated at both ends, and slightly arched at the sides, probably con- sists of two connate terga. It is converted posteriorly, appa- rently by the inbending of its sides, into a complete rmg divided by vertical partitions into three compartments, to the two outer of which the perforated caudal appendages are at- tached, and into the median and dorsally emarginate one of which it is probable that the anus opens. Between the complete ring formed by the posterior end of the last tergum and the last of the series of double sterna are interposed two plates, which I take to be the sterna of the last somite; of these the posterior, which extends beyond the extremity of the body, is soft and deeply cleft im the middle line; while the anterior, which is semicircular, and covers like an operculum all but the free margin of the posterior, is firml chitinized and has its straight hinder margin entire. The ostero-lateral margins of the latter are each produced into a short cylindrical process encircled with setee and hollowed out at its extremity into a cup-like concavity, from a tubercle in the bottom of which springs an excessively long and fine and gradually tapering simple seta; this pair of setigerous pro- cesses, which have much more the appearance of rudimentary legs than of mere processes, especially in the larva, are pro- bably sensory organs of some kind ; whilst the aperture of the genital organs (which, according to Menge, to whom we are indebted for all our knowledge of the internal anatomy, open at the hinder end of the body) is probably situated in the former rather than in the anterior part of the body, where I have hitherto failed to make out any other openings but those I have described below. Organs of Respiration.—These consist of eleven tracheal arches, opening by as many pairs of minute pores, situate on —9 Mr. J. Wood-Mason on Scolopendrella. 61 the anterior faces of the leg-bases. If a moribund specimen be placed on its side under the microscope, a row of minute specks as bright as globules of quicksilver is seen, and re~ mains visible until the contractions of the tissues consequent on drying have driven all the air from the trachee ; and in specimens killed and discoloured by osmic acid, the stigmata, with the trachez running from them, are to be seen with the greatest distinctness, the latter being marked out by silvery streaks due to the presence of air. ‘The tracheal tubes are all devoid from their very origin of the spiral thickening of their walls, so characteristic of the trachez of insects. Hach of the stigmata leads into a tube which passes inwards, back- wards, and upwards, slightly increasing in calibre as it goes, and meets its fellow of the opposite side in the middle line so as to form an arch; at the point where the tubes of opposite sides meet one another there is a slight blurriness or break in the continuity of the arch; and there is an irregularity in the height of the arches, to a certain extent corresponding to the irregularity in the length of the terga already noticed. No tufts of tubes appear to be given off from the arches; and I have not as yet made out in the body any other trachez besides these metamerically arranged ones. In the head, how- ever, there are certainly trachez present; but I have not yet studied them sufficiently to be able to speak confidently about their arrangement and distribution. The huge “crateriform openings,’”’ considered by Ryder to be the stigmata, have nothing whatever to do with the respiratory apparatus, the openings of which are excessively minute. The respiratory apparatus of Scolopendrella consists, then, as far as it has yet been made out, of a series of eleven back- wardly directed arches, opening by as many pairs of minute stigmata on the anterior faces of the leg-bases. If, in addition to the posterior arch, each pair of stigmata gave off an anterior arch, and every anterior were anastomosed in the middle line to a posterior arch, we should have an arrangement precisely similar to that which we meet with in the segmentally arranged portion of the tracheal system in such a Chilopod as Greophilus, in which a similar blurriness is to be seen at the points of anastomosis of the anterior and posterior arches. ? Excretory Apparatus.—Besides the stigmata, there is on every pedigerous somite, except certainly the first, and _pos- sibly also the second, eleventh, and twelfth, a pair of huge two-lipped apertures surrounded by a low circular wall, the summit of which is defended by a circiet of movable spines. They are in the round sclerites to which the functional legs 62 Mr. J. Wood-Mason on Scolopendrella. appear to be attached; and they therefore are posterior to the rudimentary legs. If a specimen be placed for a short time whole in a solution of hematoxylin, the everted mouths or the coagulated excreta collected upon these become deeply coloured by the reagent, so that the ventral surface of the animal is marked conspicuously with a double row ot large round black- violet spots. An accident unfortunately happened to the spe- cimen thus treated before I had had an opportunity of actually counting and noting down the number of openings that had been coloured; and I have been obliged to suggest that the round sclerites of the second, eleventh, and twelfth pairs of legs may be imperforate, though | fully believe that they are perforate like the rest. These openings possibly lead into glands which are homologous with the nephridia of Peripatus and with the glandular pouches of Machilis and Campodea; their exact morphological value is only to be determined by means of sections, which I hope shortly to have an opportunity of making. ‘They are no doubt the apertures mistaken by Ryder for the stigmata, and which are stated by Scudder to be big enough to admit the tips of the legs. Postembryonic Development.—Menge, according to Ryder’s synopsis of his paper, met with a young animal provided with only eleven pairs of legs, and concluded that it was the first pair which was wanting; I, on the contrary, have never tailed to recognize the first pair by its characters at any stage, and I am confident that it is one of those in possession of which the animal leaves the egg. Newport and Ryder both noticed ‘‘ specimens of different ages with nine, ten, eleven, and twelve pairs of legs.” I can confirm their observations, which prove that a pair of legs is added at each moult; and I have succeeded in making out the position of the germinal region. In larve provided, in addition to the three-jointed first pair of legs which properly belong to the head, with seven pairs of rudimentary and seven pairs of functional legs, nine terga (ex- clusive of those which respectively carry the pediform third cephalic and the caudal appendages) are present, or two more than the number of double pairs of feet. It is difficult, owing to the manner in which the terga seem to have been thrown out of correspondence with their double sterna, to determine with certainty which these apparently apodous terga are; but they appear to me to be the fourth and seventh (the fifth and eighth it the third gnathites are reckoned in with the ambu- latory legs) and the dorsal ares of the somites to which the fifth and sixth pairs of rudimentary feet belong.