PALAMONTOGRAPHICAL SOCIETY. VOL. LXXI. THE WEALDEN AND PURBECK FISHES. . Part III. Paces i—viul, 105—148; Puarrs XXI—XXVI. Title-page and Index. THE PLIOCENE MOLLUSCA. Part IV. Pages i—xii, 463—483. Title-page and Index to Vol. I. THE PALAOZOIC ASTEROZOA. Parr IV. Paces 169—196. THE CAMBRIAN TRILOBITES. Parr V. Paces 89—120; Prares XI— XIV. IssuED FoR 1917. California Academ Y of Seiences RECEIVED BY PURCHASE Al8o")) + Digitized by the Internet Archive in 2011 with funding from California Academy of Sciences Library htto://www.archive.org/details/monographofbriti04spen PALMONTOGRAPHICAL SOCIETY. NEO VERW EMH Sen xr CONTAINING 1. THE WEALDEN AND PURBECK FISHES. Part III. By Dr. A.S. Woopwarp. Six Plates. 2. THE PLIOCENE MOLLUSCA. Part IV. By Mr. F. W. Harmer. Title-page and Index to Vol. I. 3. THE PALAOZOIC ASTHEROZOA. Part IV. By Dr. W. K. Spencer. Twenty-six Text-figures. 4. THE CAMBRIAN TRILOBITES. Part V. By Mr. P. Laxr. Four Plates. ISSUED FOR 1917. g o \ ‘\ LONDON: PRINTED FOR THE PALASONTOGRAPHICAL SOCIETY. AGENTS FOR THE SOCIETY DULAU AND CO., LTD., 34-86, MARGARET STREET, W. 1. APRIL, 1919. THE PALASONTOGRAPHICAL SOCIETY was established in the year 1847, for the purpose of figuring and describing British Fossils. Each person subscribing One Guinea is considered a Member of the Society, and is entitled to the Volume issued for the Year to which the Subscription relates. The price of the Volume to Non-subscribers is TWENTY-FIVE SHILLINGS NBT. Subscriptions are considered to be due on the Ist of January in each year. The Annual Volumes are now issued in two forms of Binding: 1st, with all the Monographs stitched together and enclosed in one cover; 2nd, with each of the Monographs in a paper cover, and the whole of the separate parts enclosed in an envelope. Members wishing to obtain the Volume arranged in the LATTER FORM are requested to communicate with the Secretary. Most of the back volumes are in stock. Monographs or parts of Monographs already published can be obtained, apart from the annual volumes, from Messrs. Doutav anv Co., Lrp., 34-36, Margaret Street, London, W. 1, who will forward a complete price list on application. Members desirous of forwarding the objects of the Society can be provided with plates and circulars for distribution on application to the Secretary, Dr. A. Smira Woopward, British Museum (Nat. Hist.), South Kensington, London, 8.W. 7. The following Monographs are in course of preparation and publication : The Cambrian Trilobites, by Mr. Philip Lake. The Paleozoic Asterozoa, by Dr. W. K. Spencer. The Ordovician and Silurian Mollusca, by Dr. Wheelton Hind. The British Bellerophontacea, by Dr. F. R. Cowper Reed. The Phocene Mollusca, by Mr. F. W. Harmer. The Pleistocene Mammalia, by Prof. 8S. H. Reynolds. Owing to scarcity of paper, the Council has decided to omit from the present volume the usual lists of members and publications. Full particulars can be. obtained from the Secretary. Members deceased during 1917: Dr. C. T. Clough, Sir Charles Holcroft, HK. J. Power, Hsq., and Miss A. F. Yule. | New member: Dr. Wyatt Wingrave, ANNUAL REPORT OF THE -COUNCHL FOR THE YEAR ENDING 3lsr DECEMBER, 1916. READ AND ADOPTED AT THE ANNUAL GENERAL MEETING, HELD AT THE APARTMENTS OF THE GEOLOGICAL SOCIETY, BURLINGION HOUSE 30th MARCH, 1917. Dre. HENRY WOODWARD, F.R.S., Prestpenr, IN THE CHAIR, Tne Council in presenting its Seventieth Annual Report, regrets that, owing to the various difficulties of existing circumstances, its publications still remain in arrear. Paleontological research continues to make progress, and there is no lack of offers of Monographs to the Society ; but authors are hindered by many draw- backs, and the increased cost of publication necessarily reduces the amount of the annual issue. The volume for 1915, which was ready for distribution in October, 1916, contains another instalment of Mr. W. K. Spencer’s Monograph of ‘Palzozoic Asterozoa,” with four plates, and the first part of a Monograph of ‘ Wealden and Purbeck Fishes,” by Dr. A. Smith Woodward, with ten plates. The volume for 1916 is planned to contain instalments of the Monographs of ‘“‘Phocene Mollusca,” “Paleozoic Asterozoa,” “Cambrian ‘Trilobites,’ “ British Graptolites,” and “ Wealden and Purbeck Fishes,” altogether with twenty-six plates. The delay in the publications again increased the balance at the bank, and the Council resolved, from patriotic motives, to invest £400 in Exchequer Bonds, 1920, bearing interest at 6 per cent. Among members who have died during the year, the Council desires especially to refer to Mr. C. T. Clough, Mr. Bedford McNeill, Mr. Clement Reid, and 4 Miss A. F. Yule. These were all valued supporters of the Society, and Mr. Clement Reid had not only served on the Council but had also contributed an index to the Monograph of the “ Devonian Fauna ” by the Rev. G. F. Whidborne. To replace the losses sustained, the Council would welcome the help and personal influence of the members in making the work and needs of the Society more widely known among those who are interested in the study of fossils. It would also appreciate the more sympathetic co-operation of the various Field Clubs and Natural History Societies. The thanks of the Society are due to the Council of the Geological Society for permission both to store the stock of back volumes, and to hold the Council Meetings and Annual General Meeting in their apartments. In conclusion, it is proposed that the retiring members of the Council be Dr. Kitehin, Mr. Oke, and Dr. Strahan; that the new members be Mr. H. A. Allen, Mr. E. Heron-Allen, Rev. H. N. Hutchinson, and Dr. C. T. Trechmann; that the President be Dr. Henry Woodward ; the Treasurer, Mr. Robert 8. Herries; and the Secretary, Dr. A. Smith Woodward. Annexed is the Balance-sheet. ( NGUUVMA “FL 'S “ZI6L Y86 YYW J ONWT “Gd M sLoyI PNW ne “JOINSVOL, Na@TIVY “VY H ‘SHINN ‘GQ Lagaoy ‘spuog senbeyoxa ‘yueo ted 9 QOFRF pur ‘Weory aA “gueo sed Fp YOTF 04} oF puv ‘yo0jQ peyeprpostoH ‘ywep red e [RIVN ONEF OF ydtedea OYA Woes OsTR GALT 9M + 402I109 aq 0} JL puy pur ‘saayonoa ay} YYIM4t portedutoo ‘yunodoe esoqe oy} PeUTUILXE GALT] OAK 8 SIL 8c0le 8 GI 8c0lF 6 {8 Wile = 0 0 OST qunosoy psodeq ZS & 991 qUnod.V JUeIMO—yurg 7ev sourleg 0 0 OOF ° spuod Jonbeyoxg -yueo aed g Ut JUETU4SeAUT OL IL 06 qisodeq, wo 4sareyUy ® © 0G FO POURANSUI JFRIDATE-YUV 6 SLC — ; wLoTT IVA ‘yueo ted Fp QOTF pur (xey ‘Ne howl : to11e ut pred tonditosqns pewangey AULOOU SS2]) Y90}G “quoo aod g [RIVN OOGF WO spueplarq 6 210 OS ioe 0) © ke : (avod [) xq, omoouy predoy 6 a0 ; a yued i? SIR Ste PHT “OO F nen ‘sassepy Aq sapeg 0 &L0 : "JoJo G@—sesreyo AWeq ) ALS © SIaq Mey, 0} Jos YORq Fo sepeg 0 elo : . . . QoURINSUT aly ‘wUNTUELg, > F110 sloquieyy Aq pred aseriied +, Ls : : - KTOTOTZRIS PUB 90RISOg GSS 0 OL Ze wMUeIoMOY §A.1v}a.109G \) 2 Vw =—=—— == fé (O 1oe © 2 5 eo Suryem pue sururid edAyo[[09 0 9 9 9 2Z16L = i S © BA ; ; STOTLAYSN][E SUIMBICT 0 2 F&I LPL. 9T6T “ ce SL ae * XTX TOA ‘wounqrysrp pur Suppoed ‘surpurg OMG Sek pal ales F161 —stordriosqng s1equieyy 9 SL ’ XTXT TOA {990 ‘seded ‘ourjuitg TL &1 889 © qunoo. YW 4S] ULory ooULpeg JOT rea 2 ae Sh (TE es OS as “UT ‘OLGL GSTS saquavag: 01 “OT6L IST Auwnune mods ° m6) “ATUASVAY food “WW SOSH ‘SHIMMHH “S LUAGOU HiIM LNMOOoV NI ALHIOOS IWOIHAVUVOLNOW TVd SAL Council and Officers elected March, 1917. President. HENRY WOODWARD, Ese., LL.D., F.R.S., F.G.S. Vice-Presidents, F. A. Baruer, Esq., D.Sc., F.R.S. | G. J. Hinps, Esq., Pu.D., F.R.S. Rey. Canon Bonney, D.Sc., F.R.S. EK. T. Newton, Hsq., F.R.S. Council. H. A. Auuen, Esq., F.G.S. | Joxnn Hopkinson, Esq., F.LS., F.G.S8. C. W. Anprews, Hsq., D.Sc., F.R.S. | Rev. H. N. Hurcuinson, M.A., F.G.S. G. Barrow, Esq., F.G.S. Miss M. S. Jounston. : Miss M. C. Crosrrep. C. T. Trecumann, Esgq., D.Sc., F.G.S. H. Dewey, Esq., F.G.S. | §. Hazzumpinr Warren, Esq., F.G.S. Watcor Gisson, Ese., D.Sc., F.G.S. Pror. W. W. Warts, LL.D., F.R.S. Hersert L. Hawxrns, Ese., M.Sc., F.G.8. | Henry Woops, Esea., M.A., F.R.S. E. Heron-Auten, Esq., F.L.S., F.G.S. | Grorce W. Youne, Esa., F.G.S. Treasurer. Rospert S. Herrizs, Hsq., M.A., F.G.S. Secretary. A. SmitruH Woopwarp, Esq., LL.D., F.R.S., British Museum (Nat. Hist.), South Kensington, London. S.W. 7. otal Secretaries. Bath— Rev. H. H. Winwoop, M.A., F.G.S. Hertfordshire—J. Horxinson, Hsq., F.G.S. Berlin—Messrs. FriepuinpEer & Son. Oxford—Pror. W. J. Souuas, F.R.S. Cambridge—H. Woops, Esq., M.A., F.R.S. Staffordshire—Dr. Wueruton Hinp, F.G.S., Palzontographical Society, 1917. iWals FOSSIL FISHES ENGLISH WEALDEN AND PURBECK FORMATIONS. BY ARDHUR SMI Ee WOODWARD, LL.D:, F-.R.S., KEEPER OF THE DEPARTMENT OF GEOLOGY IN THE BRITISH MUSEUM; SECRETARY OF THE PALHONTOGRAPHICAL SOCIETY, PART IL. Pages 105—148, i—vili, Phares XXI—XXVI (1ncLUDING TITLE-PAGE AND INDEX). LONDON: PRINTED FOR THE PALHONTOGRAPHICAL SOCIETY. Aprit, 1919. by @ ' » ‘ , . " : ¥ ® : ’ Y - ty ° ! a et il PRINTED BY ADLARD AND SON AND WES’ NEWMAN, LID., LONDON AND DORKING. 7 / \ : ’ 7 \ — - ' ‘ N \ PALAVONTOGRAPHICAL SOCLE'PY. INSPEEUTED MDCCCXLVIT. VOLUME FOR 1917. LOND ON : MDCCCCXIX. THE FOSSIL FISHES OF THE ENGLISH WEALDEN AND PURBECK FORMATIONS. ORDER OF BINDING AND DATES OF PUBLICATION. ISSUED IN VOL. PAGES PLATES PUBLISHED FOR YEAR Title-page and Index -- Sly April, 1919 1—48 xe 1915 October, 1916 49—1()4. XI—XX 1916 February, 1918 105—148 i=). 0.00 Tony 4 April, 1919 ELE, FOSSIL FISHES ENGLISH WEALDEN AND PURBECK FORMATIONS. BY ARTHUR SMITH WOODWARD, LL.D., F.R.S:, KEEPER OF THE DEPARTMENT OF GEOLOGY IN THE BRITISH MUSEUM; SECRETARY OF THE PALHONTOGRAPHICAL SOCIETY. LON DION: PRINTED FOR THE PALZONTOGRAPHICAL SOCIETY. 1916—1919. ; . ‘ i ra . bi : 1 : ‘ r r - = =e 1 ~ ' aD. : tad . “¥- 0 > . - .) ; " PRINTED BY ADLARD AND SON AND WEST NEWMAN, LTD., LONDON AND DORKING. SYSTEMATIC INDEX. INTRODUCTION BIBLIOGRAPHY ... 2 SYSTEMATIC DESCRIPTIONS Subclass HLasMOBRANCHIL ... Order SELACHII Family CrEsrracrontTip... Hybodus a = basanus —- ensis — parvidens striatulus strictus Hybodont Cephalic Spines Acrodus — ornatus Asteracanthus = verrucosus —— semiverrucosus = granulosus Hyleobatis #8 -- problematica Subclass TELEOSTOMI a hs ap Order CRrossOPTERYGII Family C@LacanrHip® Undina — purbeckensis Order ACTINOPTERYGII Family PaLmoniscip® Coccolepis —- andrewsl — sp. Family SemronoTip® Lepidotus — minor notopterus — mantelhi Family PycnopontTip® Athrodon PAGE — bo ce CW Cw Ow Cy Subclass TErrosromr (cont.) Order ActinoprEeRyaGtt (cont.) Family Pycnopontip® (cont.) Athrodon intermedius Mesodou = daviesi = parvus Eomesodon barnesi — depressus Microdon —- radiatus Coelodus a Soe = mantelli — multidens — lirudo = levidens —- arcuatus Family Macrosemim# Ophiopsis == penicillata ... — breviceps = dorsalis Histionotus — aneularis Enchelyolepis — andrewsl Family HuenarHip® Caturus : — ~ (Callopterus ?) latidens — purbeckensis tenuidens Neorhombolepis — valdensis Family Amiip® Amiopsis damoni PAGE vi SYSTEMATIC INDEX. Subclass TeLnEosromti (cont.) Order AcTINOPLERYGIL (cont. ) Family Amirpa (cont.) Amiopsis austeni Family AspIpoRHYNCHID® Aspidorhynchus — fisheri Belonostomus ! os hooley1 Family PHotrpopHoRiIp» — Pholidophorus —= ornatus . =a eranulatus — purbeckensis — brevis Ceramurus _- macrocephalus_ ... Pleuropholis ... —_ attenuata — formosa “= crassicauda — longicauda — serrata PAGE Subclass TrnHosromti (cont.) Order AcTINOPTERYGII (cont.) Family OLIGOPLEURIDS ... (Eonoscopus sp. Family LeproLePipa Leptolepis * _ brodiei Aithalion ae — valdensis ... Pachythrissops — levis = vectensis Thrissops = curtus -- molossus ... SUPPLEMENT Hybodus basanus — sulcatus — subcarimatus Lepidotus mantelli — minor SUMMARY AND CONCLUSION PAGE 121 121 121 121 122 125 126 128 129 135 136 137 138 139 139 159 140 140 140 141 nS 1 FIG. 1. Hybodus hautianus; fish showing soft parts oo sn: 2. Ditto; restoration of skeleton ... ah. 3. Hybodus basanus; restoration of skull 4. Ditto; teeth 5. Ditto; fragment of trunk 6. Acrodus anningix ; dentition 7. Asteracanthus verrucosus; dorsal fin- spine 8. Asteracanthus semiverrucosus; dorsal fin-spine ... 9. Asteracanthus granulosus; dorsal fin- spine Bp ce “an a 10. Hylzxobatis problematica; section of tooth, magnified 11. Ptychodus mammillaris; section of tooth, magnified 12. Lepidotus semiserratus ; restoration of head ane the. 08 13. Lepidotus mantelli ; restoration of head 14. Lepidotus minor ; restoration ee 15. Lepidotus sp.; occipital portion of skull 16. Lepidotus mantelli ; transverse section of skull 17. Ditto; dentition 18. Ditto; vertebrae ue 19. Athrodon intermedius; splenial dentition 20. Mesodon macropterus ; restoration PAGE 20 A9 21. bo po bo Lo © GO NS oo S FIG. OF TEXT-FIGU RES. Homesodon liassicus ; drawing of type specimen Homesodon barnesi; drawing of type specimen... f ue 3: Microdon radiatus ; restoration Celodus costze ; restoration Ophiopsis procera ; restoration... Caturus furcatus ; restoration ... Callopterus insignis ; restoration Caturus latidens ; imperfect head Aimopsis dolloi ; restoration, with scales Ditto; restoration, without scales Amiopsis austeni; drawing of type specimen... Aspidorhynchus acutirostris ; restoration Aspidorhynchus sp.; hinder portion of Sikcutll ee as ee Pholidophorus ornatus ; restoration Plewropholis attenuata, P. lonagicauda, and P. serrata; drawings of type speci- mens Pleuropholis formosa ; restoration Leptolepis dubius ; restoration... Afthalion robustus ; restoration Athalion valdensis; drawing of type specimen Pachythrissops vectensis ; head Lepidotus minor ; amended restoration PAGE —_ PHOLIDOPHORUS. 105 widely apart, are not much shorter than the pectorals; but each comprises only about 10 rays, the foremost fringed with fulera which are larger than those of the pectoral and especially stout at the base. In the original of Pl. XX, fig. 6, the foremost pelvic fin-ray is ornamented with longitudinal flutings of enamel. The dorsal fin is best preserved in the same specimen, with about 16 smooth rays which rapidly decrease in length backwards. In a larger specimen (Mus. Pract. Geol. no. 28438) there are three or four slender basal fulcra besides conspicuous fringing fulera above, and some of the fin-rays are marked by a longitudinal line of enamel. The anal fin, which is well behind the dorsal, is comparatively small with 9 or 10 rays, best seen, though crushed, in the type specimen (Pl. XX, fie. 5,a.). Its fulera are very slender and deeply overlapping, and its broad articulated rays bear some smooth longitudinal strips of enamel. The caudal fin is also best seen in the type specimen, as already described (p. 102). All the fin-rays are much expanded lamine, obliquely overlapping: their appearance of stoutness, therefore, in the fossils depends upon the direction in which they are exposed. Nearly all the scales are conspicuously ornamented with coarse plications ending in sharp prominent serrations. As counted along the course of the lateral line they are regularly arranged in from 40 to 45 transverse series; and the series above the origin of the pelvic fin comprises 13 or 14 scales, of which the seventh or eighth is crossed by the lateral line. On the flank of the abdominal region about six scales in each series are deeper than broad, that crossed by the lateral line and the one immediately below being especially deepened. The two or three lowest ventro-lateral scales are not so deep as broad; and one of these seems to be bent along its long axis to form the edge of the ventral surface of the fish. All these scales are very conspicuously ornamented by the oblique pectinations throughout their depth; but the postero-superior angle is sometimes rounded or truncated, while on the less deepened scales of the caudal region the pectinations gradually become restricted to the lower part and sometimes on the caudal pedicle disappear. Among the rhombic scales of the ventral surface (Pl. XX, fig. 8) and the dorsal border, there is also sometimes a tendency to similar reduction of the ornament. On the scales of the abdominal region the lateral line is marked only by a posterior notch and an occasional perforation; but on the rhombic scales in the hinder half of the caudal region (PI. XX, fig. 7), it forms a sharp smooth ridge, which is also occasionally perforated in the middle. There is shght irregularity in the arrangement of the scales at the imsertion of the paired fins; and on the inner side of each pelvic fin (Pl. XXI, fig. 4, plv.) there is a peculiar row of two small scales and a posterior large elongate-oval scale, less ornamented than usual. As shown by the type specimen (Pl. XX, fig. 5) a large elongate-ovoid ridge-scale, finely rugose but not serrated, occurs on the upper border of the caudal pedicle at the origin of the caudal fin. ‘There are no prominent ventral ridge-scales (Pl. XXI, 14 106 WEALDEN AND PURBECK FOSSIL FISHES. fig. 4). All the principal scales are united by a peg-and-socket joint, which is strengthened by a low vertical ridge on their inner face (Pl. XX, fig. 7a). Horizon and Localities—Middle Purbeck Beds: Swanage; Upway, near Weymouth. 2. Pholidophorus granulatus, Egerton. Plate XXI, figs. 5, 6. 1854-55. Pholidophorus granulatus, P. M. G. Egerton, Ann. Mag. Nat. Hist. [2], vol. iii, p. 484; and Figs. and Deseripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. viii, no. 4, pl. iv, figs. 1, 2. 1895. Pholidophorus granulatus, A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. i, p. 470. T'ype.—Imperfect fish ; Dorset County Museum, Dorchester. : Specific Characters—A very robust species, attaining a length of about 30 cm.; maximum depth of trunk equalling about one-third of the total length of the fish. Head and opercular bones finely tuberculated or rugose, the tubercu- lations extending over the dorsal scales of the abdominal region. Fin-rays smooth and stout, and fulera comparatively large. Pelvic fins arising far in advance of the middle point of the trunk, and the dorsal fin opposed to them. Scales large, ornamented with very fine oblique ridges, which radiate shghtly and end at the hinder margin in delicate serrations; several series of flank-scales deeper than broad; lateral line inconspicuous. Description of Specimens.—The type specimen displays well the squamation of the trunk and the paired fins; but it is deepened a little by crushing in the ventral region, and the head bones are broken and displaced. Of the median fins it exhibits only fragments. The other known specimens are still more imperfect, but they show several of the most important characters of the genus and species. One of these specimens (PI. XXI, fig. 5) is interesting as proving that in the abdominal region there is a narrow flattened ventral face between the paired fins. The roof of the skull, partly shown in Pl. XXI, fig. 6, is broad and not much arched from side to side. The parietals (pa.) and squamosals (sqg.) are not more than one-third as long as the frontals, and their external face is closely ornamented with radiating rows of fine tubercles. They are crossed by a groove for the transverse slime-canal, and their hinder margin is deeply overlapped by the supratemporals. Each frontal (fr.) is nearly twice as wide behind as in front, slightly excavated for the large orbit at the outer border, and bifureating at the front border, where the antero-external angle is less produced than the antero-internal angle, which must have rested on the mesethmoid. The median frontal suture is deeply jagged between the middle of the orbits, but otherwise only slightly wavy. A narrow supraorbital margin is nearly smooth, but the greater part of the frontal is closely ornamented by radiating rows of fine tubercles, which are fused into coarser ridges on the anterior bifurcating portion. PHOLIDOPHORUS. 107 The longitudinal slime-canal is marked by a few pores. Remains of the supra- temporal and post-temporal plates behind are also closely and finely tuberculated. The opercular apparatus is shown in inner view in Pl. XXI, fig. 5. The operculum (op.) is narrow above owing to the rounding of the postero-superior angle, and its depth to the middle of the lower border equals its maximum width. The large suboperculum (sop.) is half as deep as the operculum, and bears the usual antero-superior prominence. The preoperculum is much expanded at its angle, and the interoperculum is relatively small. The opercular bones and remains of branchiostegal rays in the type specimen are finely granulated. Although the neural and hzmal arches in the vertebral axis are well ossified, the centra must have been extremely delicate, for there is scarcely a trace of them in the known specimens. The scales are regularly arranged in about 45 transverse series; and there are 16 scales in the series above the origin of the pelvic fins, the ninth from below being traversed by the slime-canal of the lateral lme. On the flattened ventral surface of the abdominal region they are rhombic and nearly equilateral, deeply overlapping, and ornamented in their exposed portion with fine radiating ridges, which end behind in serrations and pass forwards into tuberculations. On the lateral edge of this ventral area each scale is bent along its antero- posterior diagonal. On the flank.of the abdominal region the dorsal and ventral scales are also rhombic and nearly equilateral; but in each series eight or nine scales are deeper than broad, the deepest being those of the lateral line and the three horizontal rows beneath it. In the anterior series (Pl. XXI, fig. 5a) these scales are very deeply overlapping, and all are conspicuously ornamented with the fine radiating ridges, which end at the hinder border in serrations. On the principal scales the ridges cover nearly the whole of the exposed surface, leaving only a small triangular rugose or tuberculated area near the lower border; but on most of the abdominal scales they pass forwards into tuberculations or ruge. Further back and on the caudal region (fig. 5) the fine radiating ridges gradually become shorter, leaving the rest of the scale smooth; until towards the end of the caudal pedicle both ridges and serrations disappear. In the anterior part of the abdominal region (Pl. XXI, fig. 5a) the lateral line is marked only by a slight ridge and posterior notch on the scale; but further back and in the caudal region (fig. 5b) it opens by a prominent perforation on most of the scales. In all the scales of the abdominal region the peg-and-socket articulation is large, while the inner rib is broad and prominent (Pl. XXI, fig. 6a); in the hinder half of the caudal region (fig. 60) both the articulation and the inner rib disappear. There are enlarged scales round the anus near the origin of the anal fin. The position of the fins is shown in the type specimen, but they are imperfect in all known specimens. The pectoral fins, which comprise about 18 rays, are not much more elevated than the pelvic fins, which comprise 10 or 12 rays and are 108 WEALDEN AND PURBECK FOSSIL FISHES. fringed with stout fulera. The pelvic pair is inserted nearer to the pectorals than to the anal, directly opposite the origin of the dorsal fin, which begins with 5 or 6 very stout but small basal fulera, more or less enamelled, and comprises not less than 12 rays, perhaps 2 or 3 more. The anal fin must have been comparatively small; in the original of Pl. XXI, fig. 5, there are the bases of 9 rays, with traces of stout basal fulcra. Horizon and Locality.—Middle Purbeck Beds: Swanage, Dorset. 3. Pholidophorus purbeckensis, Davies. Plate XXII, figs. 1—3. 1887. Pholidophorus purbeckensis, W. Davies, Geol. Mag. [3], vol. iv, p. 387, pl. x, figs. 2—4. 1888. Pholidophorus purbeckensis, W. Davies, in R. Damon, Geol. Weymouth, ed. 3, Suppl. pl. xix, 1895. Pholidophorus purbeckensis, A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. 11, p. 460. Type.—Imperfect fish; British Museum. Specific Characters.—Attaining a length of 8—10 em. Length of head with opercular apparatus about equal to the maximum depth of the trunk and nearly one-quarter of the total length of the fish. Head and opercular bones smooth or feebly rugose; teeth stout and sometimes slightly recurved. Fulera smooth, unusually large and stout on all the fins. Pelvic fins inserted about midway between the pectoral and anal fins; dorsal fin opposed to the space between the pelvic and anal fins, with about 10 rays, the length of the foremost and longest somewhat less than the depth of the trunk at its insertion; anal fin also with about 10 rays, as elevated-as the dorsal ; length from insertion of anal fin to that of caudal fin about equal to maximum depth of trunk. Scales large and smooth, the hinder margin not serrated; those of the lateral line much deepened, some four times as deep as broad ; two scales above and below those of the lateral line ‘also moderately deepened ; lateral line forming only a feeble ridge. Description of Specimens.—The type specimen (Pl. XXII, fig. 1), obtained by — Mr. Robert Damon from the Lower Purbeck of the Isle of Portland, lacks the greater part of the head, but displays well the contour of the trunk in side-view, with fragments of all the fins. It also shows satisfactorily the squamation. Another specimen, much splintered by crushing, also figured by Davies (loc. cit. 1887, pl. x, fig. 2), gives the proportions of the head and caudal fin, and displays the characteristic large fulcra on the dorsal fin. A still finer specimen, with all the fins, is represented somewhat magnified in Pl. XXII, fig. 2, with a further enlargement of the fin-fulera in fig. 2a. A dwarf example evidently of the same species from a corresponding horizon at Teffont, Wiltshire, is shown enlarged twice in Pl. XXII, fig. 3 As shown in a specimen figured by Davies (1887, pl. x, fig. 2), and in another from Swanage (B.M. no. P. 12547), the postorbital part of the cranial roof is very PHOLIDOPHORUS. 109 feebly but coarsely rugose. So far as can be observed in other specimens, the cheek-plates, mandible, and opercular bones are for the most part smooth, but bear occasional prominent tubercles. The cheek-plates seem to be arranged as ordi- narily in Pholidophorus, but they are often much broken by crushing (as in the original of Pl. XXII, fig. 3). The large orbit as usual is crossed by a very stout parasphenoid bone; and an inner bone of the mouth, perhaps the vomer, bears a few stout conical teeth. The mandibular suspensorium is inclined forwards below, so that the quadrate articulation is beneath the hinder half of the orbit. The maxilla is gently arched, with comparatively small teeth. About half the length of the mandibular ramus is occupied by its elevated coronoid portion. As shown in the type specimen (PI. XXII, fig. 1, pop.) the narrow preoperculum is gently curved forwards below and not much expanded at the angle, where it is grooved and pitted by the slime-canal but otherwise smooth. As shown from within in Pl. XXII, fig. 3, the suboperculum (sop.) is scarcely half as deep as the operculum (op.), while the interoperculum (iop.) is large, long, and narrow. The branchiostegal rays are short and broad; and there seems to bea long and narrow gular plate in the specimen figured by Davies (1887, pl. x, fig. 2), though this interpretation is not certain. The axial skeleton of the trunk is always more or less obscured by the squamation, but a close series of vertebral centra in the form of delicate ossified cylinders is seen in side-view in B.M. no. P. 8379, and an isolated centrum occurs in end-view in the same specimen. ‘Traces of similar centra and short delicate ribs are also seen in the original of Pl. XXII, fig. 2. In the pectoral arch the supraclavicle (Pl. XXII, fig. 1, scl.) is about three times as deep as broad, with the outer face and hinder margin smooth. The narrow exposed portion of the clavicle is marked by longitudinal ridges or plica- tions. ‘Two postclavicular scales are clearly seen above the pectoral fin both in the original of Pl. XXII, fig. 3, and in B.M. no. 40635, the lower being about as broad as deep, the upper much deeper than broad, and tapering upwards. In the pectoral fin (PI. XXII, fig. 2) the foremost ray is much stouter than the others, and seems to have borne large fulcra. The pelvic fins are not much smaller than the pectorals, and their foremost ray bears at least six large and deeply overlapping smooth fulcra, which extend nearly to its distal end. The dorsal and anal fins, the former just in advanée of the latter, are similar in size and shape, each with about ten divided rays, which rapidly decrease in length backwards, and of which the foremost is frmged nearly to the end with eight or nine large and deeply overlapping smooth fulcra. The relatively large forked caudal fin, with nearly twenty rays, is similarly fulcrated, but the dozen fulcra above and below rapidly decrease in size distally and do not reach the extremity of the foremost ray. In all the fin-rays the segments between the articulations are somewhat longer than broad. 110 WEALDEN AND PURBECK FOSSIL FISHES. All the seales are smooth, with no posterior serrations. They are strengthened on their inner face with a stout vertical ridge, and those of the abdominal region are united by a large peg-and-socket articulation. They are arranged in nearly 40 regular transverse series; and above the origin of the pelvic fin the series comprises 11 or 12 scales, of which the lateral line traverses the seventh or eighth from the ventral border. In the abdominal region (PI. XXII, fig. 1a), the scales of the latéral line are from four to three times as deep as broad; the next scales above and below these are about twice as deep as broad; the next above and below are still somewhat deeper than broad; those dorsally and ventrally are smaller and nearly equilateral, or even broader than deep. The very narrow flattened ventral face of the abdominal region is covered with small rhombic scales; and there seem to have been slightly enlarged and modified scales, with two or three posterior denticulations, round the anus. In the caudal region (Pl. XXII, fig. 1) the scales of the lateral line still remain somewhat deeper than broad, and they are crossed very obliquely by the shme-canal, The other caudal scales are rhombic and nearly equilateral, with a tendency to the rounding of the hinder and upper margins. There is no conspicuously enlarged ridge-scale on the caudal pedicle above or below, but there seem to be two or three short and broad dorsal ridge-scales. The lateral line is marked only by a faint smooth ridge. Horizons and Localities —Lower Purbeck Beds: Portland, Dorset; Teffont, Wiltshire. Middle Purbeck Beds: Swanage, Dorset. : 4. Pholidophorus brevis, Davies. Plate XXII, figs. 4, 5. 1887. Pholidophorus brevis, W. Davies, Geol. Mag. [3], vol. iv, p. 338, pl. x, fig. 1. Type.—Imperfect fish ; British Museum. Specific Characters. yl stout mutation of P. purbeckensis, with a comparatively short and robust caudal region. Description of Specimens.—The type specimen (Pl. XXII, fig. 4), from the Upper Purbeck Beds, is distorted, so that the head is accidentally shortened and the abdominal region deepened, but it evidently represents a shorter and stouter fish than the Lower Purbeckian P. purbeckensis. Part of a second specimen, in counterpart in the Egerton and Enniskillen Collections, indicates an equally stout form (Pl. XXII, fig. 5). In the latter fossil the head appears to exhibit its true shape; and its length to the back of the opercular apparatus clearly equals the maximum depth of the trunk. Traces of a coarse rugosity are seen on the cranial roof. Stout conical teeth, some with a slightly curved apex, occur in both jaws of the type specimen. ] . The suboperculum is less than half as deep as the operculum in both specimens. Crushed obscure remains of the very delicate ring-vertebre are ee ved especially in the counterpart of the specimen figured in Pl. XXII, fig. CERAMURUS. Tet The pelvic, dorsal, and anal fins are rather well shown in the type specimen (Pl. XXII, fig. 4), which also retains fragments of the pectorals and caudal. The former appear to agree in all respects with the corresponding fins of P. purbeckensis, being only slightly smaller in proportion to the depth of the trunk. The scales are also evidently similar to those of the earlier species just mentioned. In both specimens they are much fractured, and nearly all are exposed from the inner face, displaying the strong vertical rib, with the peg-and-socket articulation in the abdominal region. They are, however, clearly smooth and without posterior serration. Horizon and Locality.—Upper Purbeck Beds: Upway, near Weymouth, Dorset. Genus CERAMURUS, Egerton. Ceramurus, P. M. G. Egerton, in Brodie’s Fossil Insects, 1845, p. 17. Generic Characters.—Trunk slender fusiform, and head relatively large; noto- chord persistent, surrounded with spaced ring-vertebree; ribs short and delicate. Fin-fulera few, long and slender. Pectoral and pelvic fins long, but few-rayed ; dorsal and anal fins not extended, the former in advance of the latter; caudal fin long, but probably somewhat forked. Squamation absent on flanks, except, perhaps, a rudiment anteriorly ; a short series of robust ganoid ridge-scales on both borders of the hinder half of the caudal region. Type Species.—Ceranurus macrocephalus, from the English Purbeck Beds. 1. Ceramurus macrocephalus, Hgerton. Plate XXII, fig. 7. 1845, Ceramurus macrocephalus, P. M. G. Egerton, in Brodie’s Fossil Insects, p. 17, pl. i, fig. 2. 1895. Ceramurus macrocephalus, A. S. Woodward, Geol. Mag. [4], vol. ii, p. 401; and Catal. Foss. Fishes, Brit. Mus., pt. iii, p. 489. T'ype.—Nearly complete fish; British Museum. Specific Characters.—A slender species, at least 4°5 em. in length. Length of head with opercular apparatus nearly twice as great as the maximum depth of the trunk, and contained about four-and-a-half times in the total length of the fish. Pectoral and pelvic fin-rays about equal in length; dorsal fin with about 10 rays, opposed to the pelvic pair; anal fin with 8 or 9 rays, completely behind the dorsal. Caudal ridge-scales smooth, those of the upper border especially acumi- nate, each being produced into a long point. Description of Specimens.—This species is known only by three specimens : the type discovered in the Middle Purbeck of Dinton, Wiltshire, by the Rey. P. B. Brodie (shown enlarged in Pl, XXII, figs. 7, 7a); a more imperfect fish discovered 112 WEALDEN AND PURBECK FOSSIL FISHES. in the Lower Purbeck of Teffont, Wiltshire, by the Rev. W. R. Andrews (B.M. no. P. 9850); and a nearly complete specimen from an unrecorded locality near Weymouth (B.M. no. P. 7506). The type specimen is preserved in counterpart, but the head and caudal fin are crushed and imperfect, while a vein of calcite crosses obliquely the hinder end of the abdominal region. Remains of the cranial roof show that the bones are smooth or only faintly rugose. The frontals (fr) form a symmetrical pair separated by a straight median suture, and excavated laterally by a large orbit. The parietals (pa.), which are also a symmetrical pair divided by a straight median suture, are each longer than broad, and marked behind by alarge groove for the transverse slime-canal. They are well seen again in inner view in B.M. no. P. 9850. The parasphenoid, which is displaced, is very stout. The mandibular suspensorium must have been inclined forwards, and the small fan-shaped quadrate (qu.), with its posterior cleft for the symplectic, is seen in the fossil below the front of the orbit. Remains of the opercular apparatus . show that it is smooth. The vertebral centra are delicate rings, which appear to have been arranged in a spaced series, so that in their crushed condition in the type specimen most of them are exposed in end-view. Some of those in the abdominal region of B.M. no. P. 7506 are in side-view, and shown to be slightly constricted. Towards the end of the caudal region the centra may have been incomplete, and in the upturned extremity they are apparently absent. In advance of the dorsal fin the neural arches are much shorter than their appended spines, which are loosely apposed and seem to have nearly reached the dorsal border. Beneath the dorsal fin the short neural arches bear extremely short spines. The ribs shown in the type, but best seen in B.M. no. P. 9850, are short and delicate throughout the abdominal region. The short neural and hemal spines in the caudal region are fused with their respective arches, and these also probably with the vertebral rings. Where the axis 18 upturned within the caudal fin, the hemal spines are enlarged and thickened as usual. There are no traces of intermuscular bones. The fins consist of long, slender rays, with distant articulations, and apparently not forked more than once at the distal end. Each is fringed by a few very long and slender fulera, which are conspicuous by their enamelled surface. The clavicle (cl.) is relatively large and much curved, widest below, and with a thin laminar expansion in its anterior concavity. Above the left clavicle, which is displaced backwards in the type specimen, there is a deep and narrow supraclavicle (scl.). There also seem to be remains of large, smooth postclavicular scales. Both the pectoral and pelvic fins are crushed close to the body, and display their character- istic fulera. One of the pelvic fin-supports is seen, slightly expanded proximally, much constricted mesially, more widely expanded distally. The length of the longest rays of the short dorsal fin is greater than the depth of the trunk at their insertion, and the elongated fulcra are especially stout at the base. Nine supports, PLEUROPHOLIS. 113 of which those anteriorly are stouter than the rest and somewhat winged, can be counted in front of the vein of calcite in the type fossil. The anal fin, which is slightly less elevated than the dorsal, comprises 8 or 9 rays, which, when adpressed, nearly reach the base of the caudal fin. Five fulcra are conspicuous on the anterior margin. The caudal fin, known only in the type specimen, is imperfect, and distorted upwards so that its precise shape is uncertain, but it seems to have been forked. The only traces of scales on the trunk are immediately behind the pectoral arch, but these may represent merely postclaviculars. Robust, smooth, over- lapping ganoid ridge-scales, however, are conspicuous on both borders of the caudal pedicle. The dorsal series begins above the middle of the anal fin, the scales all very sharply pointed (Pl. XXII, fig. 7b) and gradually increasing in size until they pass into the upper caudal fulcra. The ventral series comprises only three smaller and less acuminate scales, occupying the hinder half of the space between the anal and caudal fins. Horizon and Locality.—Middle and Lower Purbeck Beds: Vale of Wardour, Wiltshire. Purbeck Beds: near Weymouth, Dorset. Genus PLEUROPHOLIS, Kgerton. Pleuropholis, P. M. G. Egerton, Figs. and Descripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix, 1858, no. 7. Generic Characters.—Trunk elongate-fusiform, with rounded back and sharp ventral border; upper caudal lobe conspicuous. Hxternal bones smooth, or deli- cately ornamented with rugee and tuberculations ; sensory canal on cheek-plates with branches; mouth very small, with minute teeth; maxilla more or less arched, the oral margin convex. Vertebral centra annular; ribs short and delicate. Fulcra present on all the fins. Pelvic fins well developed, but smaller than the pectorals; dorsal and anal fins longer than deep, opposite; caudal fin forked. Squamation complete; scales thick and moderately overlapping; those of the middle of the flank excessively deepened, covering nearly the whole of it, each strengthened within by a broad rib and exhibiting a peg-and-socket articulation ; dorsal and ventral scales few, relatively small and rhomboidal. Lateral line deflected, passmg down the second or third deepened flank-scale and then traversing the uppermost row of small ventral scales. T'ype Species.—Pleuropholis attenuata, from the English Middle Purbeck Beds. Remarks.—The osteology of the head in Pleuwropholis is still very imperfectly known, but its cheek-plates seem to resemble those of Pholidophorus in being only in a single series. The most remarkable feature of the genus is the deflection of the lateral line; but it must be added that in one species from the Lithographic Stone of Bavaria Miss Mary 8. Johnston has also discovered shght traces of a lo 114 WEALDEN AND PURBECK FOSSIL FISHES. slime-canal on the deepened flank-scales of the caudal region (Geol. Mag. [5], vol. vi, 1909, p. 311), and there are similar traces in Plewropholis serrata described below (p. 121). . Pleuropholis occurs chiefly in the Lithographic Stone (Lower Kimmeridgian) of Bavaria and France, but is also known by fragments in the Wealden of Belgium (R. H. Traquair, “ Les Poissons Wealdiens de Bernissart.” Mém. Mus. Roy. Hist. Nat. Belg., vol. v, 1911, p. 45, pl. ix, figs. 1—3). Fie. 35.—a. Plewropholis attenuata, Egerton; type specimen, about twice nat. size.—Middle Purbeck Beds; Apsel Lane, Sutton Mandeville, Wiltshire. 8. Plewropholis longicauda, Egerton; type specimen, nat. size.—Middle Purbeck Beds; Swanage, Dorset. c, p. Plewropholis serrata, Egerton ; portions of flank-seales, outer (c) and inner (Dp) views, enlarged.—Purbeck Beds; Hartwell, near Aylesbury, Buckinghamshire. After Egerton. 1. Pleuropholis attenuata, Egerton. Text-figure 35a. 1854. Pleuropholis attenuatus, J. Morris (e« Egerton, MS.), Catal. Brit. Foss., ed. 2, p. 339 (mame only). 1858. Plewropholis attenuatus, P. M. G. Egerton, Figs. and Descripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix, no. 7, p- 1, pl. vii, fig. 1. 1895. Plewropholis attenuata, A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. 111, p. 483. Type.—Imperfect fish ; apparently lost. Specific Characters.—The type species [known only by one specimen 5 cm. in length |. Length of head with opercular apparatus somewhat exceeding maximum depth of trunk and contained about five times in total length of fish; caudal pedicle slender, about half as deep as deepest flank-scale. Opercular bones PLEUROPHOLIS. 115 smooth. Pelvic fins arising midway between the pectorals and the anal; dorsal fin, with 10 rays, arising opposite the origin of the anal fin, which comprises at least 12 rays, and arises nearly midway between the pectoral and caudal fins. Scales smooth, not serrated. Remarks.—This species is still known only by the type specimen discovered by Mr. H. W. Bristow, which is now missing. The above definition is based on Hgerton’s description and figure (reproduced here in 'Text-fig. 35a). Hlorizon and Locality —Middle Purbeck Beds: Apsel Lane, Sutton Mandeville, Wiltshire. 2. Pleuropholis formosa, sp. nov. Plate XXII, fig. 8; Plate XXIII, figs. 8—11; Text-figure 36. Type.—Nearly complete fish; British Museum. Specific Characters.—A slender, regularly fusiform species, attaining a length of about 7em. Length of head with opercular apparatus about equalling maximum depth of trunk, and contained from five to six times in total length of fish; caudal pedicle about two-thirds as deep as deepest flank-scale. Opercular bones smooth. Pelvic fins arising slightly nearer to the anal than to the pectorals; dorsal fin, with 9 or 10 rays, arising just behind the origin of the anal, which is somewhat larger, with 11 or 12 rays, of which the length of the foremost 1s somewhat less than the depth of the trunk at its insertion. Scales smooth, not serrated. Description of Specimens.—The type specimen, though fractured, seems to exhibit the general shape of the fish, with the complete caudal fin and enough remains of the other fins to indicate their position and proportions (Pl. XXIII, fig. 8). Parts of five smaller specimens on the same slab of limestone show various additional details; and several distorted examples obtained by the Rev. W. R. Andrews and others from the same horizon and locality confirm and extend our knowledge of the osteology of the species. All the external bones of the head and opercular apparatus seem to have been smooth, covered with shining ganoine, and marked only by the occasional ridges and pores of the slime-canals. he cranial roof slopes gently downwards and forwards, without any marked bend in the frontal region; but in the basicranial axis the parasphenoid, as seen in side view crossing the orbit (Pl. XXIII, fig. 9, pas.), is much arched, inclinmg downwards and forwards as it leaves the pro-otic region, and then turning upwards to the short ethmoid region. The orbit is very large, and there is a delicate ossification in the sclerotic. The single series of cheek- plates round the orbit is narrow, and marked only by the large slime-canal, which traverses the orbital margin as usual. The mandibular suspensorium is much curved forwards, so that the quadrate articulation is beneath the anterior half of the orbit, and the gape of the mouth is very small. The entopterygoid (Pl. XXIII, 116 WEALDEN AND PURBECK FOSSIL FISHES. fig. 9, enpt.) is a relatively large delicate lamina of bone, while the ectopterygoid (ecpt.) forms a stout bar at its lower border in front of the quadrate. The maxilla and premaxilla are unknown. The mandibular ramus (md.) is especially short and deep, and its dentary portion must have been comparatively small. There seem to be traces of minute conical teeth near the front of both jaws. The operculum, displayed partly from within, partly as an impression in Pl. XXIII, fig. 9 (op.), is not less than two-thirds as wide as deep, and narrowed towards the upper end. Its outer face is somewhat convex, and quite smooth, though marked by a feeble waviness concentric with the lines of growth. The subopereulum and interoperculum are comparatively small: the former is much wider than deep, while the latter seems to taper upwards into a point between the operculum and preoperculum. The preoperculum, seen from within in Pl. XXIII, fig. 9 (pop.), is sharply bent at the expanded angle, the tapering upper and lower Tis CH <@; es aw Fia. 86.—Pleuropholis formosa, sp. nov.; restoration, somewhat enlarged.—Lower Purbeck Beds; Teffont, Wiltshire. limbs being nearly equal in size and at right-angles to each other. It is traversed by a conspicuous slime-canal, from which two or three Straight branches radiate backwards at the angle. There are traces of large branchiostegal rays below the interoperculum. The axial skeleton of the trunk is usually obscured by the thick squamation, but delicate cylindrical vertebral centra are observable in some broken specimens discovered by the Rev. W. R. Andrews (B.M. no. P. 9851). Each of the pectoral fins comprises a dozen rays, of which the length of the longest about equals that of the head without operculum. Near its base the fringing fulcra are normal, but in its distal half they are more widely spaced and each bears an ovate expansion at its apex (Pl. XXIII, fig. 10). The pelvic fins are only about two-thirds as large as the pectorals, with not less than 6 rays and normal slender fulcra. The dorsal and anal fins are about equally elevated, with 9 and 11 rays respectively, of which the length of the foremost is less than the depth of the trunk at its insertion. As shown when the squamation is removed (Pl. XXITT, fig. 11), each ray is separated from its corresponding support by a short intercalated rod, as in the existing Amica. All the rays bifurcate once or twice distally, with wide articulations. As in the type specimen, the fulcra are PLEUROPHOLIS. APG usually slender and normal, becoming very small before disappearing distally ; but in one specimen (B.M. no. P. 6304) the fulera of the anal fin bear expansions like those already described on the pectoral fulera. The caudal fin is nearly complete in the type specimen, displaying its 16 rays, of which 4 in the middle are well spaced. Its deeply overlapping fulcra are very slender, and become minute distally before they disappear. The upper caudal lobe of the body is prominent. As shown by the type specimen, all the scales are smooth, without posterior serrations, and they are arranged in about 40 regular transverse series. All, except those near the end of the tail, are strengthened within by a broad vertical ridge, and united by a peg-and-socket articulation. The deepened flank-scale occurs in more than 30 of these series before it begins to subdivide on the caudal pedicle, being from four to five times as deep as its complete width in the front part of the abdominal region, and gradually becoming not much more than twice as deep as wide before subdivision on the caudal region. Hach scale exhibits a shghtly sigmoidal bend, and its lower end is truncated, while its upper end tapers a little as it curves forwards. Above each large flank-scale there are two other scales, of which the lower at least is deeper than wide; and there seem to be indications of the large flattened dorsal ridge-scales, such as are well seen in an example of another species of Plewropholis from the Lithographic Stone of Cirin, Ain, France, in the British Museum (no. P. 46912). The foremost upper scale is traversed by the shme-canal of the lateral line, which then passes down the second deepened flank-scale, and continues its course along a row of nearly square scales adjacent to the lower ends of the deepened flank-scales. Usually in the fossils the tubular excavation of the lateral line is exposed, but when a scale is perfect its only mark is a faint ridge. In the abdominal region there are four scales, wider than deep, beneath that of the lateral line, the lowest apparently forming the ventral ridge. At the base of the anal fin one row occurs beneath the lateral line, while in the caudal region beyond there seem to be three rows. On the caudal pedicle the deepened flank-scale is divided by a transverse suture into two, then into three scales, and the terminal scales are very small and rhombic. ‘The lateral line ends abruptly at the insertion of the lowest of the four spaced caudal fin-rays. The acytely poimted and deeply overlapping caudal ridge-scales which pass into the fulera of the caudal fin above and below are only moderately enlarged. Immature Fish (Pl. XXII, fig. 8).—The immature Pleuropholis, only about 3 cm. in length, shown enlarged in Pl. XXII, fig. 8, has a relatively large head ; but it may well be the fry of the species now described. It still lacks all the scales except the middle portion of those of the flank, and thus displays the internal skeleton. The remains of the head are much broken by crushing, but the curved parasphenoid is distinct in side view, and the relatively small mandible is observable. The course of the persistent notochord is indicated by a vacant space, but the neural and hewmal arches are well calcified. In the abdominal 118 WEALDEN AND PURBECK FOSSIL FISHES. region, the right and left halves of each neural arch are separate both from each other and from the neural spine, which is comparatively short; the ribs, which do not reach the ventral border, are very slender, but attached to rather stout triangular ossifications abutting on the notochord. In the caudal region both the neural and hemal arches are fused with their recurved spines, which are -also small. Beneath the upturned end of the notochord the hzemal arches supporting the caudal fin are much enlarged and thickened; and in‘the upper caudal lobe there are traces of a separate series of short rods below the fuleral ridge-scales. Fulera are not clear on any of the fins except the caudal, but the rays and their supports are well calcified. Six divided rays and one short simple anterior ray are seen in one of the pelvic fins. Nine and eleven divided rays respectively can be counted in the dorsal (fig. 8) and anal fins, besides a few short simple rays in front, each ray (except perhaps anteriorly) being separated from its corresponding support by a short intercalated rod, as in Amia. It may be added that there are traces of ganoine on some of the rudimentary flank-scales. White granular material, probably phosphatic, in the body-cavity may represent food. Horizon and Locality —Lower Purbeck Beds: Teffont, Vale of Wardour, Wiltshire. 3. Pleuropholis crassicauda, Egerton. Plate XXIII, figs. 12, 13. 1858. Plewropholis crassicaudus, P. M. G. Egerton, Figs. and Descripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix, no. 7, p. 3, pl. vii, fig. 2. 1395. Pleuropholis crassicaudata, A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. iti, p. 484, pl. xiv, fig. 5. Type.—Portion of fish; British Museum. Specific Characters.—As P. formosa, so far as known, but the trunk relatively deeper, its maximum depth a little exceeding the length of the head with opercular apparatus. Description of Specimens.—The type specimen in the P. B, Brodie Collection (Pl. XXIII, fig. 12) is too imperfect for specific determination, but it evidently represents the same species as a more nearly complete specimen from the same horizon and locality shown enlarged in Pl. XXIII, fig. 138. The latter may therefore be used for the specific diagnosis, as above. The type specimen (Pl. XXIII, fig. 12) seems to show the complete length of the head, with indications of the very large orbit, stained black, the short ethmoid region, and the narrow postorbitals traversed by a large slime-canal. The upper limb of the preoperculum, also with a conspicuous slime-canal, is distinct ; and the nearly complete operculum, about two-thirds as wide as deep, is seen to be smooth, but marked with a shght waviness concentric with the lines of growth. PLEUROPHOLIS. 119 The second specimen (fig. 13), of which the jaws, shown mainly m impression, are somewhat displaced forwards, exhibits also traces of an ossified sclerotic. Only fragments of the fins are preserved, but the places of origin of all except the dorsal are seen in the second specimen, where the extent of the forked caudal is also traceable. Stout deeply overlapping fulcra fringe the pelvic, anal, and caudal fins, those at the origin of the lower lobe of the caudal fin in the type specimen being displaced and especially conspicuous. The distantly articulated rays in the lower caudal lobe are especialiy well enamelled. The scales must have been in about 40 transverse series. Some of the deepened flank-scales in the type specimen exhibit an irregular waviness of the outer face, doubtless following lines of growth, while those of the second specimen are exposed from within, showing the broad vertical ridge on their inner face, and the peg-and-socket articulation. The caudal scales preserved in the type specimen are clearly not serrated, while those in the second specimen, though bearing the internal ridge, lack the peg-and-socket articulation. As shown in PI.- XXIII, fig. 15, the lateral line curves down the second deepened flank-scale to traverse the usual ventral row of nearly equilateral scales ; as shown on the tail of the type specimen, its course 1s marked by a shght smooth ridge on the outer face. Horizon and Locality.—Middle Purbeck Beds: Durdlestone Bay, Swanage, Dorset. 4. Pleuropholis longicauda, Egerton. Plate XXIV, figs. 1,2; Text-figure 35. 1858. Plewropholis longicaudus, P. M. G. Egerton, Figs. and Descripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix, no. 7, p. 3, pl. vii, fig. 4 : 1895. Plewropholis longicaudata, A. 8. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. ili, p. 483. T'ype.—Imperfect fish; apparently lost. Specific Characters.—Imperfectly known, but attaining a length of about 9 em., and the head with opercular apparatus occupying somewhat more than one-sixth of this length. Probably distinguished from all other known species by the depres- sion of the head, which seems to have been scarcely more than half as deep as the middle part of the trunk. Scales smooth, not serrated ; the rhombic dorsal and ventral scales often produced to a sharp point at their postero-inferior angle. Description of Specimens.—The type specimen (Text-fig. 358, p. 114), which was in Mr. W. R. Brodie’s Collection, cannot now be traced, and the description and figure given by Egerton are insufficient to diagnose the species. One specimen in the British Museum, however, from the Middle Purbeck Beds of Swanage, is labelled “ Pleuropholis longicaudus”’ by Egerton, and two other specimens from the same formation and locality also seem to belong to this species. It may, therefore, probably be defined as above. The head seems to be crushed upwards in the type specimen. Its compara- 120 WEALDEN AND PURBECK FOSSIL FISHES. tively small size is best shown in the original of Pl. XXIV, fig. 1, but the bones are so much broken by crushing that their outlines are rather obscured. The relatively large orbit is bounded behind, below, and in front by the single series of smooth cheek-plates, which are traversed by the usual circumorbital slime-canal. The gape of the mouth is evidently small. The opercular bones, partly seen also in Pl. XXIV, fig. 2, are smooth. The large angularly-bent preoperculum is marked only by the groove of the shme-canal. The operculum is about two-thirds as wide as deep, and the suboperculum is relatively small. The interoperculum seems to be triangular in shape and deeper than wide, its apex rising between the lower end of the operculum and the preoperculum. Delicate ring-vertebrze and short slender ribs are exposed by the removal of the scales in the specimen labelled by Egerton (B.M. no. P. 1101). The bases of about mine very stout rays are seen spread out in the pectoral fin of Pl. XXIV, fig. 1 ; and the foremost pectoral ray in fig. 2 bears a regular series of very slender fulera. The pelvie fins, which are shown in two specimens to arise midway between the pectorals and the anal, also consist of unusually stout rays. The dorsal and anal fins arise directly opposite each other, but are incom- pletely known. The scales are clearly all smooth without any posterior serrations. The depth of the deepest flank-scale, above the pelvic fins, slightly exceeds four times its complete width (fig. 2a). The rhombic dorsal and ventral scales are often pro- duced into a sharp point at their postero-inferior angle, and both the dorsal and ventral ridge-scales are sharply pointed behind (figs. la, 2a). Two .rows of scales intervene as usual between the principal flank-scales and the dorsal ridge- series, the lower being slightly the deeper; while five small scales occur below each principal flank-scale as far back as the pelvic fins, the uppermost being traversed by the lateral line. The ventral scales become fewer behind, as already described in P. formosa (p. 117), and the stout ventral ridge-scales are compara- tively small. Horizon and Locality.—Middle Purbeck beds: Swanage, Dorset. 5. Pleuropholis serrata, Egerton. ‘Text-figure 35c, p. 1858. Pleuropholis serratus, P. M. G. Egerton, Figs. and Descripts. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix, no. 7, p. 5, pl. vii, figs. 5—9. 1895. Pleuropholis serrata, A. 8S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. m1, p. 487. T'ype.—Imperfect fish ; collection of late Dr. John Lee, Hartwell. Specific Characters.—Imperfectly known, but a comparatively stout fish attaining a length of about 10 cm. Head and opercular bones smooth. Scales also smooth, but those of the deepened flank-series with fine oblique serrations on the hinder border. LEPTOLEPIS. 121 Description of Specimens.—All the known examples of this species are much crushed and broken, but it is easily distinguished from the other Purbeckian species by its less elegant proportions and by the serration of the principal flank-scales. Both the head and opercular bones are shown to have been smooth. The vertebral centra are preserved as delicate cylinders, with very little constriction. The fulera on the anal fin are very slender. The fine oblique serration of the principal flank-scales has already been described and figured by Egerton, who also notes the broad thickened band on the inner face connected with the peg-and- socket articulation (Text-fig. 350, p, p. 114). There is an occasional opening for slime-apparatus in these scales, but the lateral line as usual clearly passes along the row of small scales immediately below. The dorsal and ventral scales do not appear to be serrated. Horizon and Localities.—Purbeck Beds: Hartwell and Bishopstone, Bucking- hamshire. Family OLIGorLeu tips. These are the latest primitive teleosteans which retain fulcra on all the fins. They occur chiefly in the Lower Kimmeridgian (Lithographic Stone) of France and Germany, though they also range through Cretaceous formations. Some Wealden and Purbeck fossils have been wrongly referred to Oligopleurus itself on imperfect evidence (see p. 129), but a maxilla (Pl. XVII, fig. 8), from the Middle Purbeck of Swanage, may perhaps belong to the allied genus Yonoscopus, Costa. This bone much resembles the maxilla of Megalurus and Anuopsis, but it agrees still more closely with the same bone in two specimens of Conoscopus cyprinoides, from the Lithographic Stone of Bavaria, in the British Museum (as already mentioned in Geol. Mag. [4], vol. ii, 1895, p. 151, pl. vii, fig. 9). It is much laterally compressed, and more than twice as deep behind as in front; its hinder margin is slightly excavated, while its anterior end is produced into a stout incurved portion for articulation with the palatine. Its outer face is almost smooth, being very faintly rugose, and the oral margin is only slightly sinuous. The teeth do not vary much in size, and are small, but stout and conical, with the blunt enamelled apex turned somewhat inwards. They are hollow and smooth, and closely though irregularly arranged. Some teeth are broken away from the gaps observed in the series. Family Lerrouepipa. Genus LEPTOLEPIS, Agassiz. Leptolepis, L. Agassiz, Neues Jahrb. fiir Min., etc., 1832, p. 146. Oxygonius, L. Agassiz, in Brodie’s Fossil Insects, 1845, p. 16. Tharsis, C. G. Giebel, Fauna der Vorweli, Fische, 1848, p. 145. Sarginites, O. G. Costa, Atti Accad. Pontan., vol. v, 1850, p. 285. Megastoma, O. G, Costa, loc. cit., 1850, p. 287, 16 122 WEALDEN AND PURBECK FOSSIL FISHES. Genevie Characters.—Head large and teeth minute ; sclerotic ossified. Maxilla arched, with a slightly convex tooth-bearing border; mandible prominent, and dentary rising sharply into a thickened, obtuse elevation near its anterior end ; preoperculum broad mesially, with a large inferior limb, marked with radiating ridges; suboperculum large, but smaller than the trapezoidal operculum, from which it is divided by an oblique suture. Vertebral centra in the form of much- constricted cylinders, with little or no secondary ossification. Pelvic fins relatively large; dorsal fin about as long as deep, opposed to the pelvic pair or to the space between the latter and the anal; anal fin small, not much extended; caudal fin deeply forked. Scales completely covering the trunk ; no enlarged or thickened ridge-scales. Type Species.—Leptolepis bronni (i. Agassiz, Poiss. Foss., vol. 1, pt. 1, 1833, Fia. 37.—Leptolepis dubius (Blainville); restoration of skeleton, scales omitted, reduced in size.—Lower Kimmeridgian (Lithographic Stone); Bavaria. From British Museum Catalogue of Fossil Fishes. p- 13; pt. n, 1844, pp. 1338, 294), from the Upper Lias of Wiirtemberg, Bavaria, France, and England. Remarks.—The most characteristic bone of Leptolepis is the dentary of the mandible (Pl. XXIII, fig. 7). The genus has a very wide distribution both in time and space, ranging from the Upper Lias to the Lower Cretaceous in Europe, and from Spitzbergen in the north to Australia in the south. The later species as a rule (e.g. Leptolepis dubius, Text-fig. 37) exhibit more secondary ossification in the vertebre than the earlier species; but a Kimmeridgian form from King Charles Land (Ll. nathorsti, A. S. Woodward, Bihang K. Svensk. Vet.-Akad. Handl., vol. xxv, sect. iv, no. 5, 1900, p. 4, figs. 2—11) and the Purbeckian species described below seem to have primitive vertebral centra like those of L. bronni. 1. Leptolepis brodiei, Agassiz. Plate XXIII, figs. 1—6. 1845. Leptolepis brodiei, L. Agassiz, in P. B. Brodie, Foss. Insects, Pp: 15, pl. 1, figs: 13. 1845. Leptolepis nanus, P. M. G. Egerton, in P. B. Brodie, op. cit., p. 15, pl. i, fig. 5. rc crm. LEPTOLEPIS. 123 1845. Oxygonius tenuis, L. Agassiz, in P. B. Brodie, op. cit., p. 16, pl. i, fig. 4. 1850. Sarginites pygmexus, O. G. Costa, Atti Accad. Pontan., vol. v, p. 285, pl. vi, figs. 6—8. 1850. Megastoma apenninum, O. G. Costa, loc. cit., vol. v, p- 287, pl. vi, figs. 9, 10. 1853. Sarginites pygmxus, O. G. Costa, loc. cit., vol. vii, p. 7, pl. i, fig. 4. 1853. Megastoma apenninum, O. G. Costa, loc. cit., vol. vii, p. 8, pl. i, fig. 3. 1879. Leptolepis neocomiensis, F. Bassani, Verhandl. k. k. geol. Reichsanst., p. 164. 1882. Leptolepis neocomiensis, F. Bassani, Denkschr. k. Akad. Wiss. Wien, math.-naturw. CL, vol. xlv, p. 204, pl. ii, figs. 1—5. 1895. Leptolepis brodiei, A. 8. Woodward, Geol. Mag. [4], vol. ii, p. 150, pl. vii, figs. 5,6; also Catal. Foss. Fishes Brit. Mus., pt. iii, p. 515. 1912. Leptolepis brodiei, F. Bassani and G. D’Erasmo, Mem. Soc. Ital. Sci., XL [8], vol. xvii, p. 229, pl. iv, fig. 6. 1915. Leptolepis brodiei, F. Bassani and G. D’Erasmo, Paleont. Italica, vol. xxi, p. 12, pl. i, figs. 4—6. T'ype-—Imperfect fish; British Museum. Specific Characters.—A small species, attamimg a length of about 5 cm., but usually smaller. Length of head with opercular apparatus exceeding the maximum depth of the trunk, and contained about four times in the total length of the fish ; width of caudal pedicle at least half the maximum depth of the abdominal region. Vertebree from 40 to 45 in number, about half being caudal; the centra smooth ; the neural and hemal spines in the caudal region nearly straight. Pelvic fins arising about midway between the pectoral and anal fins, opposite to the anterior half of the dorsal, which has 10 or 11 bifurcated rays besides 2 or 3 shorter simple rays in front; anal fin with about 7 rays, arising nearer to the caudal than to the pelvic fins. Description of Specimens.—The type specimen, which is shown enlarged in Pl. XXIII, fig. 3, is a little distorted by the crushing upwards of the ventral border of the hinder abdominal region, while its caudal region is imperfect and lacks the caudal fin. The clavicles of the fish may also be slightly crushed backwards. It shows, however, most of the characteristic features of the species. ‘The second specimen figured by Brodie is similarly crushed, and is important as displaying the distinctive shape of the dentary bone (Pl. XXIII, fig. 4). Other specimens in the Brodie Collection, and still finer examples discovered by the Rev. W. R. Andrews, nearly complete our knowledge of the species. Two of these seem to show the true shape of the trunk and the proportions of the caudal fin (PI. XXIII, figs. 5, 6). All these fishes have the appearance of immaturity, with a relatively large orbit, which is often marked by a black stain. The head and opercular bones are smooth, and the slime-canals are relatively large, as shown especially by the frontals when exposed from below (B.M. no. P. 7635). The slender parasphenoid is nearly straight, but curves upwards a little both in front and behmd. The mandibular suspensorium is inclined much forwards, so that the articulation is beneath the middle of the orbit. In one specimen discovered by Rev. W. R. Andrews (B.M. no. P. 6305) minute teeth seem to occur on the slender arched maxilla, which has 124. WEALDEN AND PURBECK FOSSIL FISHES. a thickened upper border. In three specimens the ceratohyal is shown as a simple hour-glass-shaped bone, without any ossified filament connecting its ends. The preoperculum, as usual, is sharply bent at its angle, with a relatively large lower limb; and there seem to be two or three ridges radiating backwards from the slime-canal on the slight expansion at the angle. There are not less than 10 branchiostegal rays, of which the foremost are relatively small, slender, and spaced. The exact number of the vertebre is uncertain, but there are about 22 in the abdominal region and at least 20 in the tail. About four are comprised within the branchial region, and there are five or six in the upturned end which supports the caudal fin. As shown both by the type specimen and by others, the centra are delicate constricted cylinders pierced by a considerable remnant of the noto- chord, and their outer surface is smooth, not strengthened by longitudinal ridges. The neural arches are longest in the anterior half of the abdominal region, where they support loosely-apposed stout neural spines as far back as the origin of the dorsal fin (Pl. XXIII, fig. 3). Beneath the dorsal fin the neural arches are much shortened, without separate neural spines, and in the caudal region they are also short, sharply inclined backwards, and symmetrical with the haemal arches. The slender arched ribs extend nearly to the ventral border, and the expanded -hemal arches supporting the caudal fin are all separate (Pl. XXIII, fig. 5). Intermuscular bones, very delicate, are seen only lying across the neural spines in the abdominal region. As shown in both the specimens figured by Brodie (re-figured in Pl. XXIII, figs. 3, 4), the pelvic fins are not much less elevated than the pectorals. They comprise 7 or 8 rays, and seem to be inserted opposite the front half or the middle of the dorsal, their position varying in the fossils according to the manner in which they are crushed. The dorsal fin is especially well seen in the type specimen, where its maximum depth somewhat exceeds that of the trunk (fig. 3). Its foremost three rays are short and simple, gradually increasing in length; next there are 10 or 11 rays which bifurcate, and are distantly articulated in their distal half and slightly diminish in size backwards. Of the fin-supports the foremost two or three are fused together at an acute angle, while above the others there are distinct traces of the short intercalary pieces which are well known in Amia and several fossil Amioids. The remote anal fin, best seen in Pl. XXIII, fig. 6, is small, and comprises only about 7 rays, rapidly shortening backwards. Its rays also bifurcate and are distantly articulated in their distal half. The forked caudal fin is especially powerful (Pl. XXIII, figs. 5, 6), with distantly-articulated bifurcating rays, of which the five or six shortest in the middle of the fork are spaced. Stout sigmoidally-bent fulcral rays are seen at its base both above and below (fig. 6). The thin cycloidal scales are often seen in the fossils, marked only by the concentric lines of growth; but no enlarged or thickened ridge-scales have been observed. SO ~ AATHALION. 125 It may be added that in one of the specimens figured (Pl. XXIII, fig. 5, c.) the intestine is conspicuous, filled with white fecal matter. Immature Fishes—The type specimen of the so-called Leptolepis nanus, which is re-drawn enlarged in Pl. XXIII, fig. 2, is obviously an immature example of Leptolepis much shortened by distortion, and there is nothing to distinguish it from “. brodiei. Below and in front of the large orbit, which is stained black, the characteristic dentary bone is conspicuous. The telescoped vertebra irregularly overlap, but the crushed dorsal and pelvic fins remain almost in their natural relative positions. The base of the caudal fin is widened by the distortion. There can also be no doubt that the immature fishes named Ovygonius tennis by Agassiz are very young individuals of Leptolepis, almost certainly of L. brodiet. Their relatively large and delicately ossified vertebral column is a well-known mark of immaturity.’ The type specimen, which is re-drawn enlarged in Pl. XXIII, fig. 1, is made a little slender by crushing, but not otherwise distorted. Its skull is missing, but the orbit is marked by a black stain, and the characteristic jaws are seen. The relative width of the opercular apparatus is also clear. The feebly ossified vertebral centra, in close series, are much deeper than long, not constricted, and apparently about 40 in number. Shght traces of the pectoral fins and the small remote anal fin are preserved, while the dorsal and pelvic fins are nearly complete, though depressed by crushing. The large forked caudal fin is also well displayed. Among other specimens labelled by Brodie, one in a group in the British Museum (no. P. 7634) exlibits very clearly the ascending process of the dentary bone, and others show that the fins must have been as in L. brodiet. Horizon and Locality.—Lower Purbeck Beds: Vale of Wardour, Wiltshire. Specifically indeterminable fragments of Leptolepis have also been found in the Wealden. Among them may be specially noted the dentary bone of the mandible shown enlarged in P]. XXIII, fig. 7. Genus AAETHALION, Minster. Athalion, G. von Miinster, Neues Jahrb. f. Min., ete., 1842, p. 41. Generic Characters.—As Leptolepis, but dentary bone of mandible gradually deepening from the symphysis backwards without any marked thickening, and vertebral centra much strengthened by secondary ossification in fine longitudinal ridges. Type Species—Aithalion knorri (Clupea hnorri, H. D. de Blainville, Nouv. Dict. d’Hist. Nat., vol. xxvii, 1818, p. 351), from the Lower Kimmeridgian (hitho- graphic Stone) of Bavaria. 1 W. CG. McIntosh and A. T. Masterman, The Life-Histories of the British Marine Food-Fishes (1897), p. 415. 126 WEHALDEN AND PURBECK FOSSIL FISHES. Remarks.—This genus occurs chiefly in the Lithographic Stone of Bavaria, France, and Northern Spain (A. vidali, H. EH. Sauvage, Mem. R. Acad. Ciene. Barcelona [3], vol. iv, no. 35, 1903, p. 15, pl. 1, fig. 2). One species has been identified from the Wealden of Belgium (4. vobustus, R. H. Traquair, Poiss. Weald. Bernissart, Mém. Mus. Roy. Hist. Nat. Belg., vol. v, 1911, p. 50, pl. xi), and the same or a closely allied form is recorded from the Lower Cretaceous of Castella- mare, Naples (F. Bassani and G. D’Hrasmo, Mem. Soe. Ital. Sci. XL [3], vol. xvii, 1912, p. 284, pl. in, fig. 3, pl. vi, figs. 1, 2, text-figs. 13—15; also.G. D’Krasmo, Palzont. Italica, vol. xxi, 1915, p. 15, pl. 1, fig. 8, text-fig. 22). Dr. Traquair’s ~ Sy Ss SS yp 11 Fic. 38.--#thalion robustus, Traquair; restoration of skeleton, scales omitted, reduced in size.— Wealden; Bernissart, Belgium. After R. H. Traquair. br., branchiostegal rays; cl., clavicle; mn., mandible; me., maxilla; o., orbit; op., operculum ; pop., preoperculum ; s.0., cheek-plates ; s.op., subopereulum. sketch of the restored skeleton of the Wealden A. robustus is reproduced in Text- fig. 3 | 1. Athalion valdensis, A. S. Woodward. Text-figure 39. 1907. Leptolepis valdensis, A. S. Woodward, Ann. Mag. Nat. Hist. [7], vol. xx, p. 98, pl. i. Type.—Imperfect fish ; British Museum. Specific Characters.—A stout Species attaiming a length of about 40 em. Length of head with opercular apparatus exceeding the maximum depth of the trunk, which equals about one-third the length of the caudal fin, and would probably equal about one-fifth of the total length of the fish. Vertebre 60. Pelvie fins arising midway between the pectoral and anal fins, opposite the front half of the dorsal, which arises much nearer to the occiput than to the caudal fin and comprises 18 to 20 r arising slightly nearer to the caud from the pectoral arch to the base ays; anal fin with about 14 rays, : al than to the pelvic pair. Scales rather large and very deeply overlapping, some feebly crimped. Description of Specimen.—The type specimen (Text-fig. 39) is still unique, AATHALION. 127 but exhibits most of the characters of the species in the counterpart halves of a slab of clay. The mandibular suspensorium is clearly inclined forwards, so that the articulation of the lower jaw must have been directly beneath the hinder part of the orbit. The hyomandibular bone (him.) bears a rather lone process for the suspension of the operculum (o0p.), which is too imperfect to show its shape completely. The angle of the preoperculum ( pop.) is much expanded, and its tapering ascending limb is upright. The suboperculum (sop.) must have been about four times as broad as deep. I ifteen branchiostegal rays (br.) can be counted, the upper seven being expanded and in close series, the lower eight being Fia. 39.—Mthalion valdensis, A. 8S. Woodward; type specimen, nearly one-half nat. size-—Weald Clay ; Southwater, Sussex. British Museum, no. P. 10440. br., branchiostegal rays; cl., clavicle; hm., hyomandibular ; op., operculum: pop., preoperculum ; pft., post-temporal; sci., supraclavicle; sop., subopereulum. \ narrower bars and more widely spaced. All the opercular apparatus is smooth, not ornamented. The total number of vertebree is about 60, half bemg in the abdominal region. The centra are about as long as deep in the anterior part of the caudal region, but are somewhat shorter than deep both in the abdominal and in the hinder part of the caudal region. They are well ossified, and their primitive double cone is strengthened by secondary bone arranged in fine, close, longitudinal ridges. The ribs are stout, apparently borne on very short transverse processes, and extending to the ventral border of the fish. The fixed neural and heemal arches in the caudal region are also stout and gently arched. The hinder end of the vertebral column turns only slightly upwards, and its hemal arches are expanded without fusion. ‘’he intermuscular bones are much obscured by the scales in the fossil, but there are traces of them above the vertebral column in the abdominal region, and both above and below this column in the caudal region. The post-temporal bone (pft.) is a thick plate, almost triangular in shape, and the supraclavicle (sc/.) is a deep and narrow bone. The clavicle (cl.), as shown in impression, is expanded into a large smooth plate above the pectoral fin, which 128 WEALDEN AND PURBECK FOSSIL FISHES. is inserted close to the ventral border. When adpressed to the trunk this fin extends at least half-way to the insertion of the pelvic fins. The latter are smaller than the pectorals, and their supports are a pair of elongated thin lamine, which meet in the middle line and are thickened along their outer borders. The dorsal fin arises well in front of the middle point between the occiput and the caudal fin, comprising 18 to 20 rays, of which the three foremost are short, undivided, closely pressed together, and gradually increase in length. The length of the fourth or longest dorsal fin-ray somewhat exceeds two-thirds of the depth of the trunk at its insertion. The anal fin resembles the dorsal, but is much smaller, and comprises only 13 or 14 rays. The remains of the caudal fin-rays show that they are comparatively stout and closely articulated. The fuleral scales at the base of the upper caudal lobe are especially stout, and are continued up the foremost ray as a short fringe. The scales are relatively large, cycloid, and smooth, occasionally with feeble traces of a radiating pectination at the hinder border, but usually exhibiting structural lines, including wavy concentric markings. ‘They are scarcely displaced in the fossil, and are seen to be deeply overlapping, with the exposed area narrow and deep. he lateral line is scarcely traceable, but seems to produce a shght depression along some scales in a series above the vertebral column. Remarks. The fossil thus described evidently belongs either to Leptolepis or to Aithalion, but the absence of the mandible leaves its reference to one or other of these two genera uncertain. It was originally assigned to Leptolepis, but the extent of the intermuscular bones and the close articulation of the caudal fin-rays are suggestive rather of Mthalion; its general resemblance to the species of Aithalion deseribed by Traquair from the Wealden of Bernissart, Belgium, is indeed noteworthy. It may, therefore, best be placed provisionally in the latter genus. Its number of vertebrae exceeds that of all the known species of both Leptolepis and Mthalion, except A. vidali from the Upper Jurassic of Spain. Horizon and Locality.—Weald Clay: Southwater, Sussex. Genus PACHYTHRISSOPS, novum. Parathrissops, C. R. Kastman (non Sauvage, 1875), Mem. Carnegie Mus. Pittsburgh, vol. vi (1914), p. 428. Generic Characters—Head as in Leptolepis, but the elevation of the dentary relatively broad and less thickened. Vertebral centra much strengthened by secondary ossification in fine longitudinal ridges, short and deep in the abdominal region, sometimes longer in the tail. Pelvic fins relatively large; dorsal and anal fins acuminate, the dorsal about as long as deep, arising opposite or just in advance of the origin of the anal fin, which is equally deep and usually more PACHYTHRISSOPS. 129 extended; caudal fin deeply forked. Scales very delicate, often not preserved in the fossils. Type Species.—Pachythrissops levis, from the English Purbeck Beds. Remarks.—The two species defined below were originally referred in error to Oliyopleurus, and are proved by the new specimens now described to belong to the Leptolepidz. They seem to be generically identical with a fish from the Lithographic Stone of Bavaria named Parathrissops furcatus by Eastman (Mem. Carnegie Mus. Pittsburgh, vol. vi, 1914, p. 423, pl. lix, fig. 2), which is distinguished by the characters of its dorsal and anal fins. The generic name Parathrissops, however, is preoccupied by Sauvage (Bull. Soc. Sci. Yonne, vol. xlv, pt. ii, 1891, p- 37). The species also bear some resemblance to Hurystethus brongniarti (H. EH. Sauvage, Bull. Soc. Géol. France [3], vol. vi, 1878, p. 629, pl. xiii, fig. 2), from the Kimmeridgian of Morestel, Ain, France, but this fish is too imperfectly known for precise comparison. 1. Pachythrissops levis, sp.nov. Plate XXIV, figs.5—5; Plate XXV, figs. 1—3. 1890. Oligopleurus (7) vectensis, A. 8. Woodward, Proc. Zool. Soc., p. 346, pl. xxviii, figs. 2—4, pl. xxix, figs. 1—3. Tupe.—\Immature fish ; British Museum. Specific Characters.—The type species, probably attaining a length of 50 cm., but usually smaller. Length of head with opercular apparatus much exceeding maximum depth, also much exceeding distance between paired fins, and occupying nearly one-quarter of total length of fish. Operculum smooth, but with slime-pit defined by two ridges on outer face at point of suspension ; preoperculum with few radiating ridges near the angle. Vertebre 35 in abdominal, nearly 30 in caudal region ; the centra of the latter longer than the former, and marked by a sharp lateral ridge. Dorsal and anal fins arising directly opposite, the former with about 18, the latter with shghtly more than 20 rays. Description of Specimens.—The type specimen (Pl. XXV, fig. 1) is a small fish, which must probably be regarded as immature. It is shown in direct side view, apparently not distorted, but its vertebral axis is not well preserved, and the ribs are scarcely seen. All the known larger specimens are fragmentary, and one of these (Pl. XXIV, fig. 4) was wrongly referred to Lepidotus minor by L. Agassiz, Poiss. Foss., vol. 11, pt. 1 (1844), p. 269, pl. xxixc, fig. 12. ; The head is much crushed and broken in the type specimen, but enough is clear both in this and other specimens to identify with the same species the roof of a skull shown in Pl. XXIV, fig. 3. Here the specimen is somewhat flattened by vertical crushing, but the bones are complete as far forwards as the front of the orbit. The occiput is well ossified, and its upper portion is formed by a supra- occipital in the middle with a pair of epiotics at the sides. The supraoccipital 1 130 WEALDEN AND PURBECK FOSSIL FISHES. (soce.) occupies the middle third, and bears a vertical median crest on its hinder hollowed face. The epiotic (epo.) is very prominent on each side, triangular in shape when viewed from aboye, nearly as long as broad, and united in a finely- toothed suture with the next otic element in front. Its upper face, like that of the supraoccipital, is smooth, and must have been overlapped by the supratemporal. Each parietal (pa.) is slightly more than twice as long as broad, meeting its fellow in an almost straight median suture, and deeply interdigitating with the frontal anteriorly. The middle of its hinder half is raised into a coarsely rugose boss, in which the partly reticulating ridges tend to radiate from the transverse groove of the slime-canal. Its anterior half is nearly smooth. Hach squamosal (sq.) is about as wide as the pair of parietals, and equally long. It unites in a slightly wavy suture with the corresponding parietal, and in small digitations with the frontal, while its outer border is somewhat concave. Its outer face is nearly smooth, with some irregular pitting and longitudinal grooving. The relatively large frontals (fr.), which also meet in a nearly straight median suture, are much narrowed between the relatively large orbits, and resemble the squamosals in the irregular erooving and pitting of the nearly smooth outer face. The postfrontals or sphen- otics (ptf.) form a conspicuous pair of smooth, truncated prominences about as long as wide. There is a well-marked median depression in the cranial roof, beginning behind between the parietal bosses, and widening and deepening to the greatest extent between the hinder part of the orbits: The whole appearance of the bones suggests a considerable development of the slime-apparatus. The otic region and the basioccipital are well ossified, and the parasphenoid is comparatively stout, bearing an elongated patch of minute teeth where it underlies the hinder part of the orbit (seen in B.M. no. 21974). In some specimens there are broken traces of very thin cheek-plates. As shown in the type specimen, the mandibular suspensorium is arched forwards, so that the articulation for the mandible is beneath the middle of the orbit. The hyomandibular is a deep and much expanded thin lamina of bone, but is known only in a crushed specimen (B.M. no. P. 4535). It is strengthened by a vertical ridge, from which a short ridge proceeds at right-angles to an elongated articular process for the operculum. The triangular quadrate is cleft behind to accommodate a rod-shaped symplectic, and articulates above with a large triangular metapterygoid. The ectopterygoid (best seen in Pl. XXIV, fig. 4, ecpt.) is an arched, thin lamina of bone tapering forwards, and the entopterygoid seems to be still thinner. It is uncertain whether these elements bore teeth. As shown in the type specimen, the premaxilla is more extended backwards than usual in Amioids; and, as seen in another specimen (B.M. no. P. 4535), it bears a single series of small but stout, hollow, conical teeth. The maxilla, of which the middle portion is broken away in the type specimen, is relatively large and arched, with a flattened and nearly smooth outer face, and the convex oral border bearing minute teeth. Its posterior half is overlapped by two PACHYTHRISSOPS. 131 supramaxille, of which the posterior is the larger, and excavated in front for the anterior, which is elongate-triangular in shape. In the mandible, the dentary bone is relatively large, and its posterior end extends along the lower border almost as far as the position of the mandibular articulation. Though well shown in the type specimen, its complete shape is better seen in the original of Pl. XXV, fig. 2. The bone is truncated at the symphysis, and gradually rises in its middle portion into a high and stout coronoid process, which inclines a little backwards and ends abruptly behind. Beyond this process the tapering posterior end of the bone 1s much shorter than in the corresponding part of Leptolepis. The lower half of the bone is bent inwards along an obtuse-angled longitudinal ridge beginning below the middle of the symphysis, and this face is marked by large pits and a groove, which indicate a considerable development of slime-apparatus. The outer face is for the most part smooth, but there is a little rugosity near the oral border, which (as shown in Pl. XXIV, fig. 4) bears small, hollow, smooth, and bluntly- conical teeth. The hyoid arch, seen in Pl. XXIV, fig. 4, is relatively large, the ceratohyal (ch.) being laterally compressed, mesially constricted, and deepest behind at its articulation with the epihyal (eph.). Its upper angles seem to be united by a rod of bone as in Leptolepis. The basihyal (bh.) is very short. The preoperculum (Pl. XXV, fig. 1, pop.) is sharply angulated, with the lower limb nearly as long as the upper limb, and the anterior border much thickened. This thickening is smooth and widest at the bend, from which a few coarse ridges, more or less fused into a reticulation, radiate backwards over the thin triangular expansion. The traversing slime-canal is very large. The operculum (op.) seems to have been two-thirds as wide as deep, and is also thickened along its anterior border, from which at the point of suspension a short ridge diverges at an acute angle downwards and backwards, as if to bound a slime-pit (Pl. XXV, fig. 1a). The outer face is entirely smooth. The suboperculum (sop.) and interoperculum are comparatively small, and both these and the broad upper branchiostegal rays are smooth. The lower branchiostegal rays, of which some are seen below the ceratohyal in Pl. XXIV, fig. 4 (b7.), are slender, rod-shaped, and spaced. As shown in several specimens, but especially well in the original of Pl. XXIV, fig. 4, the gill-arches bear a close series of large bony gill-rakers (y.r.) which are smooth, laterally-compressed elongated cones, each with a notch just above its base of attachment. Similar gill-rakers appear ‘to occur in Leptolepis (B.M. no. P. 3674), Athalion (B.M. no. 37042), and Thrissops (B.M. no. P. 917). The vertebrz in the type specimen (Pl. XXV, fig. 1) are in undisturbed series, but they are somewhat broken, and not so well seen as in some of the portions of larger individuals. About 35 can be counted in the abdominal, 26 in the caudal region. The centra are all well ossified, the primitive double cone being thick and forming two wide rims, between which the secondary ossification is in fine longi- 132 WEALDEN AND PURBECK FOSSIL FISHES. tudinal ridges, producing a striated appearance on superficial view. When a centrum is isolated and exposed on the articular face (Pl. XXV, fig. 3), a median perforation is seen for a persistent strand of the notochord. All the abdominal vertebral centra are deeper than long, with gently rounded sides, and their appended arches are loosely articulated. The foremost centrum is not united with the basioccipital, but (as shown in Pl]. XXIV, fig. 4) it is peculiar in consisting of two fused discs, which are limited by a sharp line, the front disc bearing a slight prominence above for the support of the first neural arch, the second bearing a similar pair of slight prominences below to carry the first pair of ribs. The second centrum (sometimes also the third centrum) again exhibits prominences, but all the other abdominal centra are pitted for the reception of both the neural arches and ribs. The caudal vertebral centra are more elongated, about as long as deep, and their secondary ossification is disposed so as to form a sharp median longitudinal ridge on each side. Their appended arches are more firmly fixed in the sockets than those in the abdominal region, even if they are not fused. The arches are almost destroyed in the. type specimen, but they are seen in others, as in the fragment represented in Pl. XXIV, fig. 5 The neural arches are compara- tively small and delicate, and unite by large anterior zygapophyses, but they are obscured in the abdominal region by the numerous well-developed intermuscular bones which overlie them. In the caudal region the neural and hemal arches are nearly symmetrical, and sharply curved backwards, and a few intermuscular bones occur both above and below the vertebral centra. The stout gently-curved ribs extend to the ventral border of the fish, each with a shghtly expanded articular head and a wide groove along its anterior or outer face. The stout clavicle, of which the upper half is shown in PI. XXV, fig. 1 (c/.), bears a large lateral expansion which is nearly smooth, only marked by a few vertical ridges and grooves or wrinkles at the upper end. The long and narrow supraclavicle (scl.) is similarly ridged, and traversed by a large slime-canal. The pectoral fin must have been relatively large, its rays when adpressed to the trunk (as in the type specimen) reaching two-thirds of the distance to the insertion of the pelvic fins. The pelvic fin-supports (Pl. XXIV, fig. 5, plv.) are long and narrow lamine, widest at the articular end, tapering forwards, strengthened by a rib-like thickening along the outer edge, and apparently fixed together along the thin inner edge. The pelvic fin-rays, about 10 in number, are deeply imbricating and closely articulated distally. The dorsal and anal fins are shown in the type specimen to be acuminate in front and directly opposed, but their details are better . seen in other specimens. In the dorsal fin there are about 18 rays, of which the anterior four are simple and gradually increase in length, while the fifth is the longest, and this and the following are divided and articulated distally (B.M. no. P.4536). The foremost support is fan-shaped, bearing the first three rays (Pl. XXIV, fig. 5, d.), and the other supports are winged at the articular end. b PACHYTHRISSOPS. 1358 The anal fin is as deep as the dorsal and closely similar, but more extended, probably with not less than 23 rays. The long foremost support is rod-shaped, and the wings at the articular ends of the other supports are short. The forked caudal fin is well shown in the type specimen, with the step-shaped articulations of its thicker rays. All the hemal spines within the base of the caudal fin are stont, and two bearing the middle rays are slightly expanded. There are no traces of fulcra on any of the fins. Remains of rather large cycloidal scales are seen in the original of Pl. XXIV, fig. 5, but they must have been very thin, and are usually absent in the fossils. Remarks. —When examples of Pachythrissops levis were first described, they were provisionally ascribed to the Wealden species treated below ; but the form is readily distinguished by the characters of the opercular apparatus and the sharp- ness of the lateral ridge on the caudal vertebrae, besides by the proportions of the head. Horizon and Locality—Middle Purbeck Beds: Swanage, Dorset. 2. Pachythrissops vectensis, A. 5. Woodward. Plate XXIV, figs. 6, 7; Plate XXV, figs. 4,5; Text-figure 40. 1890. Oligopleurus vectensis, A. S. Woodward, Proc. Zool. Soc., p. 346, pl. xxviii, fig. 1. 1911. Oligopleurus vectensis, R. H. Traquair, Poiss. Wealdiens de Bernissart (Mém. Mus. Roy. Hist. Nat. Belg., vol. v), p. 47, pl. x. 1913. Oligopleurus vectensis, E. 8. Goodrich, Proce. Zool. Sov., p. 84. Type.—Head; British Museum. Specific Characters.—Attaining a length of a little more than a metre. Length of head with opercular apparatus about equal to the distance between the paired fins. Operculum apparently without slime-pit, smooth, or faintly rugose, but fimbriated at the postero-superior border; preoperculum with a few strong radiating ridges spaced over the lower limb. Vertebrze 35 in abdominal region ; centra in caudal region not longer than those in abdominal region, without any sharp lateral ridge, but slightly indented above and below to produce a broad rounded lateral ridge. | Fins imperfectly known.| Scales ornamented with sparse pustulations, and more or less fimbriated at the hinder border. Description of Specimens.—The type specimen is an imperfectly preserved skull and mandible shown of one-half nat. size from the right side in Text-fig. 40. The greater part of a fish (Pl. XXV, fig. 4) discovered by Mr. Reginald W. Hooley, F.G.S., exhibits the head and most of the vertebral axis, besides some remains of fins. Other more fragmentary specimens make known a few additional details. The skull is always more or less crushed and broken, but many of its principal features are shown in the fossils. As seen in the type specimen, there is a well- 134. WEALDEN AND PURBECK FOSSIL FISHES. ossified supraoccipital, bearing a vertical median crest on its posterior face; and on either side of this there are remaims of an equally well-ossified epiotic. These bones are exposed as a narrow rim at the posterior border of the cranial roof. As in P. lexvis, each parietal bone is longer than wide, and the squamosal is relatively wide, though not much longer than the parietal. The large frontal bones, as shown in the type specimen and in Mr. Hooley’s fish (Pl. XXV, fig. 4), are narrowed between the orbits; but, as also shown in Mr. Hooley’s specimens, they are much expanded in the postorbital region and overlap the well-ossified postfrontals to an undetermined extent. The parietals, sqyuamosals and frontals are marked only by fine radiating ridges and an occasional trace of the slime-canal, Fic. 40.—Pachythrissops vectensis, A. S. Woodward ; type skull, right lateral view, one-half nat. size.— Wealden ; Isle of Wight. British Museum, no 42018. ag., articulo-angular; d., dentary ; enpt., entopterygoid; g., gill-rakers; hm., hyomandibular; moplt., metapterygoid ; pma., premaxilla; qu., quadrate ; so., portion of hinder cheek-plate. but along the middle of the cranial roof there is a well-marked depression, which is widest and deepest between the hinder part of the orbits. The type specimen proves that the ethmoid region is comparatively small. Fragments of very thin cheek-plates occur in the type specimen (Text-fig. 40, sv.) and in the original of Pl. XXV, fig. 4; and a single broad series is seen to cover the postorbital region of the cheek in Pl. XXIV, fig. 6,s0. These plates are nearly smooth, but are marked with shght radiating ridges or fimbriations. They are also traversed by the slime-canal near the orbital border. The mandibular suspensorium curves forwards so that the articulation for the mandible is beneath the hinder part of the orbit. The hyomandibular (Pl. XXV, fig. 5) is much expanded at the upper end, with an apparently double-headed articulation; and, as in other fishes in which PACHYTHRISSOPS. 135 the preoperculum is relatively large, the process (p.) for the suspension of the operculum is much elongated. Just below the latter process the bone is antero- posteriorly compressed and rises to a sharp vertical crest along its outer face. The triangular quadrate (Text-fig. 40, qu.) is cleft postero-superiorly for the rod-shaped symplectic (Pl. XXV, fig. 4, sy.), and articulates above with a large triangular metapterygoid (mpt.). Its articular condyle for the mandible is “somewhat constricted from the main part of the bone, and has a robust inwardly- directed process arising from its base. The entopterygoid (enpt.) 1s an elongated thin lamina of bone, bluntly pointed in front, truncated behind, shghtly convex on the oral face, and inclined inwards towards the parasphenoid. The ectopterygoid (Pl. XXV, fig. 4, ecpt.) is a narrower elongated lamina, more rapidly tapering in front. It is toothless along the lower border, but its oral face, like that of the other pterygoid plates, has not been seen. The premaxilla, imperfectly shown in the type specimen (Text-fig. 40, pmw.), is comparatively small, but longer than deep. The large maxilla (Text-fig. 40 and Pl. XXV, fig. 4, ma.) is arched, and its outer face is nearly smooth, marked only in places with a faint rngosity ; its convex oral border exhibits the points of attachment of clustered minute teeth. Its posterior two-thirds are overlapped by two supramaxille, of which the posterior is the larger and excavated in front for the anterior, which is very long and narrow and tapers forwards. The outer face of the posterior supramaxilla is shghtly rugose, and bears a ridge along the lower margin of its antero-superior extension. The articulo-angular bone of the mandible (Text-fig. 40, ag.) is short and deep, and its lower portion is ornamented with fine longitudinal ruge. The very large dentary (d.), which is imperfectly known, is evidently truncated at the symphysis, and its lower half is sharply bent inwards, separated from the upper half by an obtuse longitudinal ridge. The hyoid arch, partly seen in the original of Pl. XXV, fig. 4, is relatively large, and the upper branchiostegal rays, attached to the epihyal, are especially large smooth lamineze of bone (br.). The preoperculum, incomplete and abraded in the type specimen, is best seen in Pl. XXIV, figs. 6 (pop.), 6a. It is sharply angulated, with a relatively large lower limb, and a great smooth expansion behind. The anterior border is much thickened and smooth, and from this thickening six or seven coarse ridges radiate over the outer face of the lower limb. The operculum (op.) is imperfect in all the specimens, and the proportions of the suboperculum and interoperculum are uncertain. The operculum seems to have been smooth or only faintly rugose, except at its postero-superior border, where it 1s finely fimbriated. A single vertebral centrum attached to the occipital region of the type specimen is completely ossified, deeper than wide, and very short, marked on the sides by fine striations which extend between a thickened rim anteriorly and posteriorly. The neural and hemal arches are inserted in pits. As shown by the 136 WEALDEN AND PURBECK FOSSIL FISHES. large fish (Pl. XXV, fig. 4), all the vertebral centra are of this type, except that they are generally longer in proportion to their depth. There seem to be 54 or 35 in the abdominal region, but the number of caudals is uncertain. The centra in the caudal region are scarcely longer than those in the abdominal region, but they differ in exhibiting a slight lateral indentation above and below a rounded median lateral ridge. The neural arches in the abdominal region are long and slender, but most of them are broken and displaced, and obscured by the overlapping intermuscular bones. The stout, gently-arched ribs are well shown, reaching the ventral border, each impressed by a longitudinal groove. The neural and hzmal arches in the caudal region are firmly fixed in their sockets in the centra. The remains of the clavicle (Pl. XXV, fig. 4, ¢/.) and supraclavicle (scl.) inelude a wide, nearly smooth, exposed portion; and a large smooth plate of bone (w.) shown behind the skull is probably the post-temporal, much expanded, as in Thrissops. The long pectoral fin-rays ( pet.) are very closely articulated distally. The pelvic fins (plv.), with slender supports, are much smaller than the pectorals, and are evidently inserted nearer to the anal than to the latter. Of the anal fin (a.), only a fragment remains with at least 17 rays. As the anterior supports are relatively long and stout, this fin must have been acuminate. The dorsal and caudal fins are unknown. Scales are seen in some of Mr. Hooley’s specimens, all large, thin, and cycloidal, and deeply overlapping. They are most conspicuously marked by the concentric lines of growth; but some exhibit sparse pustulations, usually in rows, on the smooth exposed face, besides fine fimbriations at the hinder margin (Pl. XXIV, fies). ‘ Horizon and Localities —Weald Clay: Atherfield, Isle of Wight; Berwick, Sussex. Genus THRISSOPS, Agassiz. Thrissops, L. Agassiz, Poiss. Foss., vol. ii, pt. i, 1833, p. 12. Generic Characters. Head as in Leptolepis, but smaller, and the dentary bone with a broader, less thickened elevation. Vertebral centra much strengthened by secondary ossification in longitudinal ridges, of which the median lateral is usually very prominent ; no centra much deeper than long. Ribs especially stout. Pelvic fins relatively small; dorsal and anal fins acuminate and opposite, the former small and short-based, the latter much extended; caudal fin forked. Scales thin, com- pletely covering the trunk; no enlarged or thickened ridge-scales. Type Species.—Thrissops formosus (Lu. Agassiz, Poiss. Foss., vol. ii, pt. i, 1833, ne THRISSOPS. 137 p. 12; vol. ui, pt. u, 1844, p. 124, pl. xv), from the Lithographic Stone (Lower Kimmeridgian) of Bavaria. Remarks.—Thrissops seems to range in HKurope from the Middle Jurassic (Oxfordian) to the Lower Cretaceous; but without a knowledge of their cranial osteology, the systematic position of the later species usually ascribed to this genus must remain uncertain. They closely approach the Ichthyodectidze or Chirocen- tride. 1. Thrissops curtus, sp. nov. Plate XXVI, fig. 1. Type.—Imperfect fish; British Museum Specific Characters. —At least 16 em. in length. Length of head with opercular apparatus nearly equalling maximum depth of trunk, and contained from four to five times in total length of fish ; maximum depth of trunk contained about two-and-a- half times in leneth from pectoral arch to base of caudal fin. Pelvic fins half as large as pectorals, inserted nearer to the anal fin than to the latter ; dorsal fin, with 13 rays, arising behind the origin of the anal fin, which is shehtly more elevated in front and comprises 30 rays; caudal fin very deeply forked and lobes slender. Description of Specimen.—The type and only known specimen (Pl. XXVI, fig. 1) lacks the jaws, but is otherwise nearly complete. In the skull the ethmoidal region is very short and small, and the parasphenoid is seen crossing the relatively large orbit. A short ridge inclined upwards at the back of the occiput may perhaps be the thickened upper border of a triangular supraoccipital crest such as seems to occur in Thrissops formosus (Brit. Mus. no. P.¥v17). The preoperculum is vaguely shown to be much expanded at the angle and marked with several fine radiating ridges. The operculum, which is smooth, is widest below, and its maximum width is at least three-quarters of its depth. It seems to show a peculiar shme-pit near its point of suspension like that already described in Pachythrissops levis (p. 131, Pl. XXV, fig. la). The suboperculum, which is also smooth, is slightly more than one-third as deep as the operculum. The vertebral centra are evidently well ossified, but are not clearly seen except at the end of the tail, where they bear the usual sharp median lateral ridge. Over twenty vertebrze can be counted in the caudal region. The neural arches in the abdominal region are separated from the neural spines, which reach the dorsal border. Some of the anterior spines of this series have a small laminar expansion at their lower end. The stout grooved ribs, of which there are over twenty pairs, reach the ventral border. The neural and hzmal arches in the caudal region are fused both with their spmes and with the corresponding centra; they are slender, short, and much inclined backwards. At least nine hemals are included in the base of the caudal fin. Intermuscular bones occur only in the dorsal part of the abdominal region. Behind the skull, the post-temporal is a large, smooth, rhomboid plate, nearly as wide as deep, 18 138 WEALDEN AND PURBECK FOSSIL FISHES. strengthened by a ridge extending diagonally from its antero-superior angle. The supraclavicle is relatively deep and narrow, and the clavicle is much arched. The anal fin comprises 27 rays, with three gradually lengthenmg fulcral rays in front, and its anterior acumination is about three-quarters as deep as the trunk at its insertion. The dorsal fin is shghtly less elevated, with only 10 ordinary rays preceded by three fulcrals. Traces of the usual thin scales are seen, none with ornament. : Remarks.—Although the abdominal part of the vertebral column in the type specimen is somewhat displaced by crushing, the ‘arrangement of the neural arches and ribs suggests that it has not been much shortened. The species is therefore peculiar in the shortness of the trunk, and it differs from the only known species from Portland (7. portlandicus, A. 8. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. ui, 1895, p. 525, pl. xvi, fig. 4) not only in this feature, but also in the more remote insertion of the dorsal fin. Horizon and Locality.—Lower Purbeck Beds: Isle of Portland. The strati- graphical position was determined by the collector of the type specimen, Mr. J. R. Short. The exact horizon of 7’. portlandicus was not recorded by the collector. 2. Thrissops molossus, sp. nov. Plate XXVI, fig. 2. T'ype.—Imperfect fish; British Museum. Specific Characters. —At least 35 em. in length. Head remarkably short and deep. Length of head with opercular apparatus nearly equalling maximum depth of trunk, and about one-fifth of total length of fish; maximum depth of trunk contained about three-and-a-half times in length from pectoral arch to base of caudal fin. Caudal fin very deeply forked and lobes slender. Description of Specimen.—There is no doubt that the fragmentary fish shown of one-half the natural size in Pl. XXVI, fig. 2, represents a hitherto unrecognised species, but it is too imperfect for precise determination. The cranium is lacking, but the adjacent remains are sufficiently undisturbed to show that the head is unusually short and deep. The ossified border of the sclerotic of the very large eye 1s well preserved, and the mandibular suspensorium and jaws are also seen. The stout rod-shaped symplectic occurs below the hyomandibular, evidently fitting into a cleft of the large fan-shaped quadrate. The pterygoid bones form an extensive laminar expansion above the maxilla, which is gently arched and bears a regular close series of small conical teeth. Of the premaxilla only a fragment remains. ‘lhe mandible is very imperfect, but its articulation is clearly below the hinder border of the orbit, and its oral border bears conical teeth which are larger than those of the maxilla. The remains of the operculum are bordered behind by part of the clavicle, and its width is thus shown to equal half the length of the SUPPLEMENT. 139 head. The lower branchiostegal rays are very slender. The parts of the trunk preserved seem to be almost in their natural position, but some of the abdominal vertebree are displaced above the fossil, while the upper iobe of the caudal fin is torn away and displaced below. The axial skeleton is typically that of Thrissops, and the middle hzmal spine at the base of the caudal fin is much-expanded. The stoutness and length of the anterior supports of the anal fin show that this must have been very deep and acuminate in front. Horizon and Locality—Middle Purbeck Beds: Swanage, Dorsetshire. SUPPLEMENT. Hybodus basanus, Egerton (p. 5). Plate XXVI, fig. 3. Mr. Reginald W. Hooley, F.G.S., has obtained from the top of the Weald Clay in the typical locality, Atherfield, Isle of Wight, the well-preserved small head partly shown in Pl. XXVI, fig. 3. In the front part of the jaws it displays some of the characteristic teeth; and at the limits of the gape of the mouth there are remains of the labial cartilages, as already described (p. 7, Pl. LI, figs. 1 a, 10). Even allowing for some vertical crushing, however, the skull clearly differs from the well-preserved specimen from Pevensey (Pl. II, fig. 1) in being relatively shorter and broader, with less widened postorbital processes. As seen from above (Pl. XXVI, fig. 3), the supraorbital flanges are well developed, and the interorbita! width exceeds half the total length of the cranial roof. The posterior depression (p.f.) is less elongated than in the best-preserved Pevensey specimen. The small rostral prominence is evidently broken away by accident. The occiput (Pl. XXVI, fig. 3a) 1s especially well shown, only abraded at its median vertical crest, which is still best seen in the skull already mentioned on p.6. The occipital face is more than half as deep as wide, and its most conspicuous feature is the large excavation for the notochord (w.) in the basioccipital region, resembling that im Notidanus (Hevanchus).' The foramen magnum (f.m.), seen above this excavation, is com- paratively small. A pair of deep pits (v.) in the cartilage flanking the foramen magnum would probably be pierced by the foramina of the vagus nerves. Hybodus sulcatus, Agassiz. The two fragments of a dorsal fin-spme named Hybodus sulcatus by Agassiz (Poiss. Foss., vol. ui, 1837, p. 44, pl. x 0, figs. 15, 16), though originally stated by 1 ©. Gegenbaur, Untersuchungen zur vergleichenden Anatomie der Wirbelthiere.—III. Das Kopfskelet der Selachier (1872), p. 120, pl. iv, fig. 2, pl. xv, fig. 2. 140 WEALDEN AND PURBECK FOSSIL FISHES. Mantell to have been obtained from the Chalk of Lewes, are generally regarded as Wealden fossils (S. J. Mackie, The Geologist, vol. vi, 1863, p. 242, and A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. 1, 1889, p. 275). A renewed examination of these fragments, however, suggests that they are from a ferruginous concretion in the Chalk, and not from any Wealden deposit. As already suspected by M. Leriche (Mém. Soc. Géol. Nord, vol. v, 1906, p. 91), they are parts of the dorsal fin-spine of a Chimeroid fish; but they still remain unique. The anterior border of the spine is less compressed to an edge than usual, and it is ornamented with a few large and irregularly arranged tubercles (not shown in Agassiz’ figures). The longitudinal ribbing of the lateral faces is coarser and more marked than in any other known Chimeroid spine. ‘The specimen may perhaps belong to a species of Ischyodus. Hybodus subcarinatus, Agassiz (p. 10). Lepidotus mantelli, Agassiz (p. 36). According to Mr. J. Wilfrid Jackson, the type specimens of Hybodus sub- carinatus and the so-called Vetrayonolepis mastodonteus (= small dentary of Lepidotus) are in the Cumberland Collection in the Manchester Museum. (IEE Ss Fia. 41.—Lepidotus minor, Agassiz; restoration with amended dorsal and anal fins, to replace the restoration given in Text-fig. 14, p. 28. Lepidotus minor, Agassiz (p. 27). Plate XXVI, fig. 4. Dr. F. Du Cane Godman, F.R.S., has lately given to the British Museum the large specimen of the stout variety of Lepidotus minor, from the Middle Purbeck Beds of Swanage, shown of one-third the natural size in Pl. XXVI, fig. 4. It is important as displaying the complete dorsal fin, which is proved to have been wrongly drawn in the restoration of the species in Text-fig. 14, p. 28. A new restoration with the dorsal and anal fins amended is accordingly given in Text- fig. 41. The specimen is much laterally compressed by crushing, so that the left SUMMARY AND CONCLUSION. 141 half of the cranial roof is bent downwards and has slipped partly beneath the right half. The mouth is also opened, and the ventral part of the abdominal region is displaced downwards. The large characteristic smooth maxilla (mz.) 1s well seen, with part of the supramaxilla, and the ectopterygoid (ecpt.) and quadrate (qu.) are exposed. ‘lhe small upper postorbital cheek-plate seems to be subdivided by a vertical suture ; the large postorbital is also divided transversely in its lower half, but this may be merely an accidental crack. The tubercular ornament of the opercular bones is unusually extensive and dense. Remains of the paired fins show their relative proportions. The enamelled fulcra in the dorsal fin are slightly curved, forming a convexly arched border; the closely divided and articulated fin-rays seem to be complete, and resemble those of LD. mantelli (see Pl. VII, fig. 7). Some of the anterior scales of the flank are coarsely serrated in their lower half, but further back the corresponding scales do not exhibit more than one denticulation above the produced postero-inferior angle, and this soon disappears at the beginning of the tail. From the produced angle, and sometimes from the denticulation above, a faint oblique ridge extends forwards over the scale. The upper slime-canal, which begins as usual on the third row of scales below the dorsal ridge, descends and becomes a little irregular near the dorsal fin. SUMMARY AND CONCLUSION. Little is added to our knowledge of the Wealden and Purbeck fish-fauna by the fossils discovered in the corresponding formations on the European continent. Even in the great collection described by Traquair,' from the Wealden of Bernis- sart, Belgium, there is only one genus, the Macrosemid Notayogus, additional to those represented among the English fossils. At Bernissart no Selachian remains are known, but in north Germany” there are teeth and spines of Hybodus much resembling those now described. In north Germany several fine specimens of Lepidotus have also been discovered,’ but of other ganoids there are only teeth and fragmentary jaws, chiefly referable to Pycnodonts. So far as known, therefore, the fishes of the Wealden and Purbeck formations are essentially Jurassic, and not mingled with any typically Cretaceous forms. Most of them are, indeed, the specialised and evidently final representatives of the Jurassic families to which they belong, and very few can be regarded as possible ancestors of fishes which followed in Cretaceous and later times. ' Rh. H. Traquair, “ Les Poissons Wealdiens de Bernissart,” Mém. Mus. Roy. Hist. Nat. Belgique, vol. vi (1911), pp. 1—65, pls. i—xii. 2 W. Dunker, Monographie der Norddeutschen Wealdenbildung. Brunswick, 1846. 8 W. Branco, “ Beitrage zur Kenntniss der Gattung Lepidotus,’” Abhandl. geol. Specialk. Preussen u. Thiiring. Staaten, vol. vi (1887), pt. 4, pp. 1—84, pls. i—viu. 142 WEALDEN AND PURBECK FOSSIL FISHES. Among the Selachians, the well-preserved skulls of Hybodus basanus are especially interesting, because they exhibit much more resemblance to those of the Notidanidee than to the skull of the modern Cestracion, to which Hybodus is commonly regarded as nearly allied. The teeth of some of the Lower Jurassic species of Hybodus, indeed, seem to pass into those of the earliest known species of Notidanus! ; just as the high-cusped teeth of the Wealden H. basanus are closely similar to some of the Middle and Upper Jurassic teeth of Orthacodus,’ which seem to pass into those of the primitive though typical Lamnidz of the Cretaceous period. Some of the more generalised Hybodonts, when better known, may therefore prove to be ancestral to several later types of sharks. Hybodus basanus is also noteworthy in having only one pair of hooked cephalic spines instead of the two pairs, of nearly equal size, which characterise the early Liassic species.® In one species of the allied genus Asteracanthus. from the Oxford Clay of Peterborough, the late Mr. Alfred N. Leeds observed that of the two pairs of cephalic spines one was much smaller than the other. There was thus probably a similar reduction of one pair in some species of Hybodus, which eventually resulted in its complete loss. The occurrence of a dwarf species of Acrodus im the Wealden is paralleled by that of a similar dwarf species in an estuarine deposit of nearly the same age in Bahia, Brazil." This is almost the last appearance of the genus, the latest known species being Acvodus levis from the Gault. No remains of Crossopterygians have hitherto been found in the Wealden, and the only specimen from the Purbeck Beds is that of the typically Jurassie Undina now described. The ornament of the scales clearly distinguishes it from the Cretaceous Macropoma. Among Chondrosteans the Palzoniscide are represented for the last time by the genus Coccolepis, which is too specialised to be ancestral to the later sturgeons. The representatives of Lepidotus are interesting as including a comparatively generalised species, 1. minor, which might even be Lower Jurassic, besides a large and highly specialised species, L. mantelli, which could not be earlier than Upper Jurassic, and might be Lower Cretaceous. The vertebral ossifications in the latter species are particularly remarkable. The Pyenodonts also comprise both generalised and moderately specialised ' Compare Hybodus polyprion, Ag., with Notidanus muensteri, Ag. (A. 8S. Woodward, Geol. Mag., [3] vol. iii (1886), p. 257, pl. vi, figs. 1—5). 2 0. Jaekel, Sitzungsb. Gesell. naturf. Freunde, Berlin, 1898, p. 139, text-fig. 2; F. Priem, Bull. Soc. Géol. France, [4] vol. xii (1912), p. 254, with figs. A large tooth apparently of Orthacodus, from the Danian of Scandinavia, has been described as Oxyrhina lundgreni, J. W. Davis, Trans. Roy. Dublin Soc., [2] vol. iv (1890), p. 393, pl. xxxix, figs: 8—13. 5 See Hybodus delabechei (Charlesworth), A. S. Woodward, Catal. Foss. Fishes, Brit. Mus., pt. 1 (1889), p. 259, pl. viii, fig. 1. * Acrodus nitidus, A. S. Woodward, op. cit. (1889), p. 297, pl. xiv, fig. 8. SUMMARY AND CONCLUSION. 143 forms, but no exclusively Cretaceous genera. The specimens of Microdon radiatus and Mesodon parvus from the Purbeck Beds are especially well preserved to show the osteology, and a study of them has led to several new observations.! There ean no longer be any doubt as to the close relationship of these fishes to the Lepidotus-lke ganoids. The Purbeckian specimens of Ophiopsis and Histionotuws make some additions to our knowledge of the osteology of the more generalised Macrosemiide, which emphasise their affinity to the Kugnathide. The curious development of large slime-pits in the preoperculum and supratemporal bones of Histionotus still awaits explanation. If the new genus Hnchelyolepis be rightly placed in the same family, its very thin cycloidal scales are particularly interesting and novel. Besides the remains of typical Hugnathide of Jurassic facies, one example of the later Cretaceous genus Neorhombolepis is described from the Wealden. Hither this, however, or a nearly similar genus also occurs in the apparently Lower Cretaceous estuarine deposit in Bahia, Brazil,’ already mentioned, while the closely-related Otomitla is found in the Neocomian of Mexico.” Amiopsis, though so closely similar to Amia, still retains the short dorsal fin which distinguishes the Jurassic members of the family. It is a Cretaceous genus. The Purbeckian Aspidorhynchus fisheri seems to be the latest species of the genus hitherto discovered. The specimens now described show much of the osteology, and suggest that the supposed close relationships of the Aspidorhyn- chide to the Lepidosteidz need further examination. The Wealden remains of Belonostomus are unfortunately too fragmentary for discussion. The Pholidophoride occur for the last time, and the Purbeckian species of Pholidophorus are interesting for the strength of their fins. P. ornatus and P. granulatus are especially similar to species from the Upper Jurassic Lithographic Stone of Germany and France. The almost scaleless Ceramurus may be regarded as a highly specialised member of the family. Some of the Purbeckian specimens of Pleuwropholis are in an unusually good state of preservation, and add to our knowledge of the osteology of the genus. Among the Leptolepide, which are also essentially Jurassic fishes, may perhaps be recognised some of the ancestors of the typical physostomous teleosteans of the later Cretaceous seas. They evidently connect the more typical “ ganoids”’ with the primitive Elopidz which are so abundant in marine Cretaceous formations. By a relative enlargement of the supraoccipital and otic bones in the skull, a 1 A. S. Woodward, “ Notes on the Pyenodont Fishes,’ Geol. Mag., [6] vol. iv (1917), pp. 385— 389, pl. xxiv. 2 A. S. Woodward, “ The Fossil Fishes of the English Chalk ” (Paleont. Soc., 1911), p. 256. 3 Otomitla speciosa, J. Felix, Paleontographica, vol. xxxvii (1891), p. 189, pl. xxix, fig. 3, pl. xxx, figs. 3—5. 144 WEALDEN AND PURBECK FOSSIL FISHES. partial fusion of the heemal spines at the base of the caudal fin, and an increased development of the intermuscular bones, some of them may have become Clupeide. By nearly the same changes, such genera as Pachythrissops and Thrissops may also have passed into the Chirocentrus-like fishes, which were as numerous in the Cretaceous fauna as the Elopines and Clupeoids, and are represented at the present day by a genus (Chirocentirus) which retains a remnant of the primitive spiral valve in the intestine." It is therefore interesting to compare the fishes of the Wealden and Purbeck estuary with those of the contemporaneous seas in the Kuropean area. It is only unfortunate that the latter are thus far very imperfectly known. Fish-remains are not uncommon in some of the marine Neocomian formations of France which seem to be contemporary with at least the later Wealden deposits, but they are all very fragmentary.” So far as determinable, nearly all of them are typically Jurassic ; though it should be remembered that these are durable fossils such as the teeth and fin-spines of sharks, and the teeth and jaws of Pyenodonts and Lepidotus. More delicate skeletons may have been destroyed beyond recognition, as suggested by the discovery of an otolith which may be Clupeoid.? Among these fossils, however, both in France and in Switzerland there are a few Selachian teeth* so closely similar to those of the Lamnidze that they evidently indicate the appearance of the modern type of shark which became so abundant and widely spread in the later Cretaceous seas. Well-preserved fishes in another Neocomian formation in the Voirons, Switzerland,’ include recognisable forerunners of the Chirocentrids (Spathodactylus neocomiensis) and Clupeoids (Crossoqnathus sabaudianus, Clupea antiqua, and Clupea voironensis), those referred to Clupea itself showing distinctly the characteristic ventral ridge-scutes. The Clupeoid Crossognathus also occurs in the Hilsthon of Hanover, which seems to correspond with the uppermost part of the Weald Clay. The marine fish-fauna of Europe before the end of Wealden times was thus distinctly in advance of the estuarine fauna so far as known, and approached the later Cretaceous fauna in its Lamnid sharks, Chirocentrids, and Clupeoids. The nearly contemporaneous estuarine deposit on the coast of Bahia, Brazil, to which reference has already been made, shows that the Lower Cretaceous fish- ' Cuvier and Valenciennes, Histoire Naturelle des Poissons, vol. xix (1846), p. 160, pl. 565. 2 M. Leriche, ‘ Sur quelques Poissons du Crétacé du Bassin de Paris,” Bull. Soe. Géol. France, [4] vol. x (1910), pp. 455—469, pl. vi. * Otolithus (Clupeidarum ?) neocomiensis, F. Priem, ‘“ Poissons Fossiles du Bassin Parisien”’ (Publ. Ann. Paléont., 1908), p. 37, text-figs. 11—14. * Lamna (Odontaspis) gracilis, L. Agassiz, Poiss. Foss., vol. iii (1843), p. 295, pl. xxxviia, figs. 2—4. Odontaspis macrorhiza mut. infracretacea, M. Leriche, Bull. Soc. Géol. France, [4] vol. x (1910), p. 459. ° B. J. Pictet, “‘ Description des Fossiles du Terrain Néocomien des Voirons” (Matér, Paléont, Suisse, ser. 2, 1858), pp. 1—54, pls. i—vii. SUMMARY AND CONCLUSION. 145 fauna of that region was essentially the same as in Europe. According to the discoveries of Mr. Joseph Mawson,’ it includes such typical survivors of the Jurassic fauna as Acrodus, Lepidotus, Megalwrus, and probably Pelonostomus, besides a few more advanced forms, among which a Chirocentrid (Chironystius mawsont) and a Clupeoid (Diplomystus longicostatus) are clearly recognisable. The only unique fish found here is a gigantic Coelacanth, Mawsonia, as bighly specialised as the Upper Cretaceous Macropoma. The fish-remains hitherto recorded from the supposed Neocomian of Mexico,’ the United States,’ and Hast Africa‘ are also of an essentially Jurassic facies. It is therefore evident that a specially rapid evolution of sharks, skates, and teleosteans occurred in Middle Cretaceous times. In conclusion, the author desires to express his thanks to the many friends who have facilitated this work. He is especially indebted to the Director of the Geological Survey, Dr. F. L. Kitchin, and Mr. H. A. Allen; to the President and Committee of the Dorset Field Club, and Captain John KH. Acland of the Dorset County Museum; to the late and present Woodwardian Professors at Cambridge, and Mr. Henry Woods of the Sedgwick Museum; to the Curators of the Museums of Devizes, Hastings, Manchester, Sherborne School, Warwick, and York; to the late Mr. Charles Dawson; and to Mr. Reginald W. Hooley. He also owes both the drawings on the plates and the new text-figures to Miss Gertrude M. Woodward. 1 J. Mawson and A. S. Woodward, ‘On the Cretaceous Formation of Bahia (Brazil) and on Vertebrate Fossils collected therein,” Quart. Journ. Geol. Soc., vol. lxiti (1907), pp. 128—139, pls. vi— viii. See also A. 8S. Woodward, Quart. Journ. Geol. Soc., vol. Ixiv (1908), pp. 358—362, pls. xlii, xlii; and D. 8. Jordan, Ann. Carnegie Mus. Pittsburgh, vol. vii (1910), pp. 23—-34, pls. v—xiii. tw J. Felix, Paleontographica, vol. xxxvii (1891), pp. 189—194, pls. xxvill—xxx. E. D. Cope, Journ. Acad. Nat. Sci. Philad., [2] vol. ix (1894), pp. 441—447, pls. xix, xx; J. W. Gidley, Proc. U.S. Nat. Mus., vol. xlvi (1913), pp. 445—448, text-figs. ]—4., 4B. Hennig, Sitzungesb. Gesell. naturf. Freunde, Berlin, 1913, pp. 309, 315. i) 19 ADLARD AND 148 PAGE Microdon = ey rb a8 ado) z= clecans aa sae Se ae ee =< Talents © vee 59. XIV; XV, 1-5 Microps a 2 - 101 Myliobatidee @) te = wa = UY Neorhombolepis ae ae ae soe — excelsus se OTS = valdensis ... = 872 eV LIL Notidanus 142 — muensterl 142 Odontaspis gracilis bus 144. — macrorhiza mut. infracretacea... 144: (Honoscopus ... ac wi ae ae abet e) ; — cyprinoides 121 Oligopleuridze 121 Oligopleurus ... an) “29 == vectensis 129, 1338 Ophiopsis a6 = ae es ee Au) — breviceps ... (5 XV, 3-12 ==) dorsalis he DWE, Ne = penicillata... FAs DWE We 24 = procera CURA Orthacodus ae # 142 Otolithus Ghescenn ?) neocomiensis ... 144 Otomitla 143 Oxygonius 121 | — tenuis 195; XXII, il Oxyrhina lundgreni ... bis 142 = paradoxa ... va ie oe Pachythrissops ae oat 128 a levis 129; XXIV, 3-5; XXV, 1-8 - vectensis 1335 XX PV,,-6; 7 ; XXV, 4, 5 Paleeoniscidee... 23 Parathrissops 128 — fureatus 129 Petalopteryx ... 80 Pholidophoride 101 Pholidophorus ee Lae OU — bechei e 101 == brevis : 110; XXIL, 4,5 — eranulatus ... 106; XXI, 5, 6 micronyx 103 SON AND WEST NEWMAN, INDEX. Pholidophorus ornatus 102: - purbeckensis Plesiodus Pleuropholis ... attenuata -- crassicauda — formosa (35 = - longicauda serrata ... Prolepidotus ... Ptychodus | Pyenodontide | Pyenodus granulatus a liassicus — mantelli microdon . rugulosus ... Sarginites — pygmeus ... Serobodus Selachi Semionotide ... Spathodactylus neoconiensis | Spheerodus Sphenonchus ... — elongatus Strobilodus purbeckensis Strophodus Teleostomi Tetragonolepis serodontens Tharsis Thectodus Thlattodus Thrissops curtus — formosus... = molossus portlandicus Typodus Undina — penicillata — purbeckensis Ureus 1 be ad | LTD., LONDON AND DORKING. PAGE XX, 5-8; XXI, 4 108; ; XXII, 1-3 26 113 114 . XXII, 12,13 XXIL 8; XRT, 8-11 114, 119; XXIV, 1, 2 114, 120 =, 20 19, 21 36, 42, 140 121 14 82 see i. sb 1375 Sev, fl ay: ee Lo 188; XXVI, 2 158 48 21 29, 22; IV, 1 82 bo Ox . _~ : . PLATE XXI. PaGe Belonostomus hooleyi, sp. noy.; left flank-scale, outer view, lacking lower end and part of outer face, one-and-a-half times nat. size.— Wealden; Atherfield, Isle of Wight. The type specimen. Collection of Reginald W. Hooley, Esq., F.G.S. 100. Ditto ; dorsal scale, outer view, three times nat. size.—Wealden; Isle of Wight. Mantell Collection (B. M. no. 28419). 100. Ditto (?); right flank-scale, outer view, one-and-a-half times nat. size.-— Wealden ; Sevenoaks, Kent. Sedgwick Museum, Cambridge. 101. Pholidophorus ornatus, Agassiz; imperfect head and abdominal region, right lateral and ventral view, one-and-a-half times nat. size.— Middle Purbeck Beds; Swanage, Dorset. Museum of Practical Geology, London, no. 28439. ag., angular; b7., branchiostegal rays; ¢l., clavicle; d., dentary; 2op., interoperculum; m., maxilla; op., operculum; orb., orbit; pet., pectoral fin; plv., pelvic fin; pop.» preoperculum ; scl., supraclavicle ; so., postorbitals; sop., sub- operculum. 103. Pholidophorus granulatus, Egerton ; greater part of fish, right lateral and ventral view, two-thirds nat. size, with some anterior flank-scales (5a) and some caudal flank-scales (50), outer view, enlarged one- and-a-half times.—Ibid. Beckles Collection (B. M. no. P. 6379). op., left operculum, inner view ; sop., left suboperculum, inner view. 106, Ditto; portion of roof of skull, upper view, showing frontals (/*.), left parietal (pa.), and right squamosal (sq.), nat. size, with some anterior flank-scales (6a) and caudal scales (66), imner view, enlarged one- and-a-half times.—Ibid. Hnniskillen Collection (B. M. no. P. 3605). L106. PALE ONTOGRAPHICAL SOCIETY, A.S.Woodward, Wealden & Purbeck Fishes. (SNA Sop. sel, op. ra ( Plate XXI. hy G.M.Woodward del et lith. Huth,imp. I-3. Belonostomus: 4-6. Pholidophorus. Fie. if Or @.9) PLATE 2XTT: Paex. Pholidophorus purbeckensis, Davies; imperfect fish, right lateral view, one-and-a-half times nat. size, with some anterior flank-scales (1 a) and caudal scales (1), outer view, enlarged three times.— Lower Purbeck Beds; Isle of Portland. The type specimen. Damon Collection (B. M. no. P. 6171). pop., preoperculum ; se/., supra- clavicle. 108. Ditto; nearly complete fish, right lateral view, one-and-a-half times nat. size, with foremost anal fin-ray and fulera (2) enlarged four times. —Ibid. British Museum, no. P. 8378. 108. Ditto; small fish, right lateral view, twice nat. size-—Lower Purbeck _ Beds; Teffont, Vale of Wardour, Wiltshire. diop., mteroperculum ; op., upper part of operculum; sop., suboperculum. P. B. Brodie Collection (B. M. no. P. 7640). 108. Pholidophorus brevis, Davies; imperfect fish, left lateral view, one-and-a- half times nat. size-—Upper Purbeck Beds; Upway, near Weymouth. The type specimen. EHgerton Collection (B. M. no. P. 1074). 110; Ditto; head and anterior abdominal region, much broken by crushing, one-and-a-half times nat. size, with some flank-scales (5a), mner new, enlarged twice.—Ibid. Enniskillen Collection (B. M. no. Eo O0/). $10. Pholidophorus limbatus, Agassiz; front of anal fin with fulera, four times nat. size, for comparison with fig. 2¢.—Lower Lias; Lyme Regis, Dorset. Egerton Collection (B. M. no. P. 1047). Ceramurus macrocephalus, Egerton; distorted fish, left lateral view, with counterpart of head (7 a), two-and-a-half times nat. size, and three Middle Purbeck Beds; Dinton, Vale of Wardour, Wiltshire. ‘The type specimen. Brodie Collection. (B. M. no. P. 7689). cl., clavicle; fr., frontal; pa., parietal; qu., quadrate ; scl., supraclavicle. oe aie caudal ridge-scales (7 b), enlarged ten times. Pleuropholis, sp.; immature fish, right lateral view, three times nat. size, with dorsal fin (8a) enlarged five times.—Lower Purbeck Beds; Teffont, Vale of Wardour, Wiltshire. Rev. W. R. Andrews’ Collec- tion (B. M. no. P. 9846). Ii7. PALZONTOGRAPHICAL SOCIETY, I917 A.S.Woodward, Wealden & Purbeck Fishes. Vey, bia. Ss : | SOK G.M.Woodward, del.et lith, Hauth,imp 1-6. Pholidophorus. 7 Ceramurus. 8. Pleuropholis. PLATE, XXII. Fig. PaGE. 1. Leptolepis brodiei, Agassiz; very small immature fish, right lateval view, four times nat. size.—Lower Purbeck Beds; Vale of Wardour, Wiltshire. The type specimen of Oxvygonius tenuis, Agassiz, P. B. Brodie Collection (B. M. no. P. 4730). 128. 2. Ditto; immature fish shortened by distortion, right lateral view, five times nat. size.—Ibid. The type specimen of Leptolepis nanus, Egerton. P. B. Brodie Collection (B. M. no. P. 7637). 125. 3. Ditto; fish lacking most of caudal fin, left lateral view, twice nat. size.— Ibid. The type specimen. P. B. Brodie Collection (B. M. no. P. 7635). iss 4. Ditto; distorted fish, three times nat size.—ltbid. P.B. Brodie Collection (B. M. no. P. 7635 a). 123. 5, 6. Ditto; two well-preserved specimens of trunk, left lateral view, twice nat. size.-—Lower Purbeck Beds; Lime Kiln Quarry, Teffont, Vale of Wardour, Wiltshire. Rev. W. R. Andrews’ Collection (B. M. nos. P. 9847, 48). c., coprolitic matter in intestine. 123. | Leptolepis, sp.; right dentary bone, inner view, twice nat. size.—Wealden (Wadhurst Clay); Broad Oaks, Brede, near Hastings. Teilhard and Pelletier Collection (B. M. no. P. 11904). 125. 8. Pleuropholis formosa, sp. nov.; nearly complete fish, left lateral view, twice nat. size-—Lower Purbeck Beds; Teffont, Wiltshire. The type specimen. British Museum, no. P. 10986. 115. 9. Ditto; head, left lateral view, three times nat. size.—Ibid. British Museum, no. P. 10955. — ecpt., ectopterygoid ; enpt., entopterygoid ; md., mandible; op., operculum; pas., parasphenoid; pop., pre- operculum. 116. 10. Ditto; foremost pectoral fin-ray bearing expanded fulcra, enlarged ten times.—Ibid. British Museum, no. P. 9851. AG. 11. Ditto; part of anal fin, showing supports, five times nat. size—Ibid. British Museum, no. P. 10986. EL6S 12. Pleuropholis crassicauda, Egerton; imperfect fish, right lateral view, twice nat. size-—Middle Purbeck Beds; Durdlestone Bay, Swanage, Dorset. The type specimen. P. B. Brodie Collection (B. M. no. P. 7647). 118. 13. Ditto; fish with incomplete fins, left lateral view, twice nat. size.—Ibid. British Museum, no. 43615. 118. PALZ ONTOGRAPHICAL SOCIETY, 1917. A.S.Woodward, Wealden & Purbeck Fishes. Plate XXlll. 1.¢ a tf A me Z AUT Fe eee aL aed | “(& BFF z eet CUTE: oO 2a Ye ue Willig, ote Jie NN \\ | Y\ LEEKS CSS ‘ Ss 3 G.M.Woodward del. et lith Huth imp is eee NSW Os e@) Ait 6) Hs: 6-13. Pleuro pirelws:. bo ey) . PLATE XXIV. PaGe. Pleuvopholis longicauda, Kgerton; head and abdominal region, left lateral view, nat. size, with some dorsal scales (1 «) and some ventral scales (1 >) enlarged four times.—Middle Purbeck Beds; Swanage, Dorset. British Museum, no. 40724. 120. Ditto; imperfect fish, left lateral view, nat. size, with some scales (2) enlarged twice.—Ibid. British Museum, no. P. 7664. 120. Pachythrissops levis, sp. nov.; roof of skull, lacking end of snout, nat. size.—Ibid. British Museum, no. P. 12212. epo., epiotic; fr., frontal; pu., parietal; pt/., postfrontal (sphenotic); soce., supra- occipital; sy., squamosal. 129. Ditto; remains of head and three anterior vertebre, right lateral view, two-thirds nat. size, with some lower teeth (4 a) enlarged twice. —Ibid. Portion of specimen figured as Lepidotus minor by L. Agassiz, Poiss. Foss., vol. 1, pt. 1 (1844), pl. xxixc, fig. 12. Enniskillen Collection (B. M. no. P. 4219). bh., basihyal; br., branchiostegal rays; ch., ceratohyal; d., dentary; ecpt., ectopterygoid; eph., front of epihyal; g.7., gill-rakers on gill-arch. 129. Ditto; middle portion of trunk, right lateral view, nat. size.—Ibid. British Museum, no. 44845. d., dorsal fin-supports and fin; plv., pelvic fin-supports with fins. 152. Pachythrissops vectensis, A. 8S. Woodward; portion of head, left lateral view, with lower expansion of right preoperculum (6a), one-quarter nat. size.—Weald Clay; Atherfield, Isle of Wight. Collection of Reginald W. Hooley, Hsq., F.G.S. op., operculum; pop., pre- operculum; so., postorbital cheek-plates. 134. Ditto; scale, nat. size.—Ibid. Collection of Reginald W. Hooley, Esq., F.G.S. 136. PAL ZONTOGRAPHICAL SOCIETY. 1917. A.S.Woodward,Wealden & Purbeck Fishes. Plate XXIV. pop G.M.Woodward del, et lith Huth imp l2> Pleuropholis. ‘37-7. Pachythrissaps, bo Or . PLATE XXV. Pachythrissops levis, sp: nov.; nearly complete fish, left lateral view, nat. size, with part of operculum (1 @) enlarged six times to show slime-pit.—Middle Purbeck Beds; Swanage, Dorset. The type specimen. British Museum, no. 40453. br., branchiostegal rays; cl., clavicle; op., operculum ; pop., preoperculum ; sc/., supraclavicle ; sop., suboperculum. 129. Ditto; left dentary, outer view, one-third nat. size.—Ibid. British Museum, no. 36083. Sl. Ditto; vertebral centrum, end view to show perforation by notochord, nat. size.—Ibid. British Museum, no. 21974. ie Pachythrissops vectensis, A. S. Woodward; imperfect fish, right lateral view, one-quarter nat. size— Weald Clay; Atherfield, Isle of Wight. Collection of Reginald W. Hooley, Esq., F.G.S. a@., portion of anal fin; ag., angular; br., branchiostegal rays; cl., clavicle; ecpt., ecto- pterygoid; ma., maxilla; pcet., pectoral fins; plv., pelvic fins; qu., quadrate; sc/., supraclavicle; sy., symplectic; «., probably post- ew) bo . — ~~ ~~ temporal. Ditto; upper part of left hyomandibular, outer view, one-half nat. size.— Wealden ; Isle of Wight. British Museum, no. 42013. p., process for support of operculum. PS. HQ 7s PALZONTOGRAPHICAL SOCIETY, A.S.Woodward,Wealden & Purbeck Fishes. Plate XXV. we ey Pe se wyoatoid pf yD) rs sit © j Ny Se Hyp, o Ay i sad On Huth imp. G@.M.Woodward del. et lith. Pachythrissops. Fic. PLATE XXVI. PaGe. Thrissops curtus, sp. nov.; right lateral view of fish, nat. size.—Lower Purbeck Beds; Isle of Portland. The type specimen. British Museum, no. P. 10612. 1SZ: Thrissops molossus, sp. nov.; left lateral view of fish, two-fifths nat. size. —Mniddle Purbeck Beds; Swanage. British Museum, no. P. 417 a. 138. Hybodus basanus, Kgerton; cranium, upper and (3 a) posterior views, one-half nat. size.—Weald Clay; Atherfield, Isle of Wight. Col- lection of Reginald W. Hooley, Esq., F.G.S. f.m., foramen magnum ; n., pit for notochord ; p.f., posterior fossa or fontanelle ; v., pair of pits into which the vagus nerves probably opened. — 139. Lepidotus ininor, Agassiz; imperfect fish, left lateral view, showing dorsal fin, one-third nat. size-—Middle Purbeck Beds; Swanage. British Museum, no. P. 12211. 140. SOCIETY, 1917. PALZONTOGRAPHICAL XXVI Plate hes. A.S.Woodward, Weaiden & Purbeck Fis Huth imp G.M.Woodward del.et lith T pninnti1te A rT 4 Palxontograpbical Society, 1917. THE PLIOCENE MOLLUSCA OF GREAT BRITAIN, BEING SUPPLEMENTARY TO S. V. WOOD’S MONOGRAPH. OF THE CRAG MOLLUSCA. BY F. W. HARMER, Hon. M.A.CaAntas., F.G.S., F.R.METS., MEMBRE HONORAIRE DE LA SOCIETE BELGE DE GEOLOGIE EB’ DE PALEONTOLOGIE. Pe ead ag Bags PaGEs 1—xii, 463—483. Title-page and Index to Vol. I. LONDON: PRINTED FOR THE PALHONTOGRAPHICAL SOCIETY. Aprit, 1919. a sere ahi « PALAONTOGRAPHICAL SOCIETY. INSTITUTED MDCCCXLVIL. VOLUME FOR 1917. LON DON : MDCCCCXIX. THE PLIOCENE MOLLUSCA OF GREAT BRITAIN, Vie dbs. | ORDER OF BINDING AND DATES OF PUBLICATION. pagne puares TSOUED IN VOE-| py pn ISTRD Title-page and Index — 1917 | April, 1919 1—200 I—XXIV 1913 | February, 1914 201—302 XXV—XXXII 1914 | July, 1915 303—461 XXXITI—XLIV | 1916 | July, 1918 THE PLIOCENE MOLLUSCA GREAT BRITAIN, BEING SUPPLEMENTARY TO S. Ve WOOD Ss MONOGRAPH OF THE CRAG MOLLUSCA. BY KF. W. HARMER, Hon. M.A.Canras., F.G.5S., F.R.METS.. MEMBRE HONORAIRE DE LA SOCIETE BELGE DE GEOLOGIE ET DE PALEONTOLOGIE. VOLUME I. LONDON: PRINTED FOR THE PALHONTOGRAPHICAL SOCIETY. 1914—1919. ’ rhe LC Th 2 y : a Ms A ees TED BY ADLARD AND SON AND WEST NEWMAN, 1-TD., LONDON a : ¢ 5 _ — a, INTRODUCTION NON-MARINE MOLLUSCA Sphyradium — edentulum Pyramidula — rysa — suttonensis Eulota — fruticum Hygromia — hispida — incarnata — rubiginosa Vallonia — pulchella... — excentrica Helicodonta — lens Helicigona arbustorum Helix 2 lactea — nemoralis — hortensis... Cochlicopa — lubrica Jaminia — muscorum — eylindracea Clausilia — plhiocena ... Succinea — elegans — oblonga ... — putris Carychium — minimum — ovatum Pomatias 12 16 — bo NG Do D'h to ww WH PW Dd iow) o> Ox — SG PAGE | SYSTEMATIC INDEX. Pomatias Harmeri Acroloxus — lacustris ... Limnea — butleyensis — palustris — Harmeri ... — pereger — Woodi — auricularia, var. acuta ... Planorbis — corneus — spirorbis... — precursor Paludestrina ... — Reevei Lithoglyphus — fuscus | Bithynia — tentaculata Vivipara — glacialis ... — media Valvata — cristata — piscinalis | Corbicula — fluminalis Spherium — corneum Pisidium — amnicum — astartoides — casertanum — supinum.. — Henslowanum DISTRIBUTION OF LAND AND FRESHWATER SHELLS OF THE ORAG... MARINE MOLLUSCA v1 Trivia ... — europea ... ne — — var. sphericulata — affinis — pisolina ... Voluta — suturalis Ancilla — Nysti Terebra — canalis — — var. costata ... — exilis p — inversa, var. costata Columbella — scripta — compta — subulata... Astyris — rosacea Cassidaria — tyrrhena... sie — hbicatenata, var. Canhami Cassis ... : i Pee Sub-genus Semicassis ... — — saburon Rostellaria “ae Sub-genus Rimella — — gracilenta Nassa ... — reticosa ... es, — — var. pulchra.... — — var. lineata ... — — var. cancellata — — var. costata ... — — var. incisa —- semireticosa — prismatica — clathrata... — emiliana ... — Cantrainu — microstoma —— jimata . — — var. anomala — serrata —- ligustica... —- labiosa — propinqua SYSTEMATIC INDEX. PAGE 59 59 Nassa monensis — Kermodei — limatula ... — consociata — elegans — granulata — Dautzenbergi — — var. simplex... — — var. minuscula — Dollfusii — — var. convexa... — pusillina... — yvenusta ... = vara VV OOdIn es, — Woodwardi — lamellilabra — — var. elegantula — spectabilis — turonica ... — ef. Edwardsi — Kennardi — — var. elongata — pumila — incrassata Desmoulea — conglobata Buecinum — undatum... , — — yar. clathrata —- — yar. striata ... — — var. cerulea ... — — var. tenera — — yar, littoralis — — var. flexuosa... == ——savoPCrassal — — yar. zetlandica = — yar. acuminata — — var. Schneideri — -— var. pulchra ANP. ADT aoe — greenlandicum —- — var. connectens — — var. patula — ciliatum ... — — var. levior — terre nove — finmarchianum ... — perdix PAGE 79 Buecinum hydrophanum — — var. tumidula — tenue — angulosum — — yar. normalis — fragile — Humphreysianum — Donovani — variabile — imexhaustum — elongatum — meridionale vars inieata — — yar. elongato-undosa — — yee, eae, ..- — Totteni ... Liomesus — canaliculatus Purpura — tetragona — lapillus — derivata ... Stenomphalus — Wiechmanni Triton — heptagonum — Woodii Murex — rudis Ocinebra — erinacea ... — tortuosa e — — var. boytonensis — —— yar. minor Urosalpinx — cinereus Trophon — clathratus — Gunner! ... — truncatus — Fabricii ... — — var. Bailyi — muricatus — —) Var valida == — yar, similis’ ... — — var. Nysti — Lamplughi Meyeria SYSTEMATIC INDEX. Meyeria alba ... Searlesia — costifer ... — — var. PB — — yar. pulchra... — — var. elongata — — var. cancellata — — var. crassa — — var. islandica — — var. monensis — Forbesi — Bjornsoni — Ravni — @yenl — Lundgren — Harrisoni — elegans — proxima ... — Nordmanni — alveolata — consocialis Parasipho — Kroyeri Anomalosipho — Verkruzeni — — yar. plicifera — altus — — var. virgata ... == — yar, costellata — Bellu — Actoni Volutopsis — Largillerti -—— norvegica Beringius — Turtoni ... — — var. minor Neptunea — contraria... — — var. typica — — var. sinistrorsa — — var. angulata —= —— “Var, IMLormis — despecta ... — — var. decemcostata — — yar. carimata — — var. subantiquata — — var. behringiana Vill Neptunea despecta, var. Cobboldiz — yar. intermedia — var. pumilio... — var. intersculpta — var. curtispira — var. subspitzbergensis antiqua ... — var. typica — var. striata ... — var. subtornata — var. icenica ... ventricosa castanea ... ignota Pusus ... longiroster lamellosus Sipho ... gracilis —_var. Coulsoni — var. elongata — var. convoluta curtus togatus — var. crassa — var. Frielei — var. brevispira — var. minor Sabin Herendeenii cordatus ... Menapiz islandicus glaber latericeus minimus... tortuosus — var. turrita ... — var. attenuata — var. lirata Olavii — var. Morchii... — var. conulus... propinquus Jeffreysianus ebur - Sarsii exiguus SYSTEMATIC INDEX. PAGE 164 165 165 166 167 | 167 168 168 169 169 | 170 | 171 | 172 | 173 173 | 173 | 174 | 175 175 | 177 | 177 178 | 178 180 181 182 182 183 183 | 184 185 186 187 | 188 189 189 190 191 191 192 193 194. 195 195 196 197 Sipho elegans... Trophon truncatus, var. Harmeri ... (?) Sipho hirsutus Family Pleurotomids Pleurotoma turricula — var. antwerpiensis ... Selysii inermis Sub-genus Hemipleurotoma — denticulata ... — plebeia — Gastaldiu Clavatula interrupta Genotia (Genota) ramosa Pseudotoma ... intorta — var. Morreni Borsonia suffolciensis Oligotoma pannus ornata festiva decorata ... bipunctula — var. proxima Drillia Brocechii ... icenorum — var. elongata — var. speciosa incrassata — var. dertomagna — var. miominor (?) — var. crassa — var. Nysti sigmoidea — var. pliomagna crispata ... emendata - galerita terebra Kendalli... 198 | Spirotropis 199 | modiola ... 22 ~ S 5) — oo wm bo mDPenwnnNnbWb nw Ww bt Ww Ww ht oo Ot me Be OO or) Iw NP Nw Ww YS WH WNW Wb by ——————— SYSTEMATIC INDEX. ix PAGE PAGE Clathurella ... DE a: ae ... 231 | Raphitoma nana __... ae 7 ua 208 — purpurea... ae one ia _. 231 | =— mitrula ... to ae 5 ait, PAO) -—— — var. minor ... one fe ... 284) — striatula... oe iy ah Pee ch} — Philberti... ie in a .. 234]! — curtistoma eer. me fs mols veel —— leutroyi :.. te aide as . Zoo | — nebula... Be sis i wee eet — concinna ... oe she 0 ... 236 | — — var. elongata 226 nf te aide — linearis ... Sis Le ate ... 23¢ | — — var. Ginnaniana ... Heb 2 bo ww — — var. equalis ... oe af ... 288 | — — var. delicatula — Cordieri ... we ne ire . 239 — levigata — hystrix .... sa a she ... 240 | Bela Bellardiella ... ee es sit ... 241 | — turricula... — gracilis ... ae Bee 5508) Seem | — scalaris ho bw bo for) SS Sa Sy Se Sa TSS t > CO DD — volutella .. ee in ae ... 242 | — — var. ecarinata ae oe see SO: — stria His ro Ae ue ... 243 | —- — var. abyssicola He ase sun St Mangilia ee Wee ae oS .. 244) — nobilis... see ee so ASiIL — costata ... ne at aa .. 244} — rugulata ... wid ies Sie ee 282 — — var. coarctata biG ae ... 245 | — — var. scalaroides sa ys ea) 260 — cerulans... a Seis das ... 246 | — — var. Schneideri a ae .. 284 — dubia... ae are fn ... 246 | — — var. bergensis ca oe a. 284 —albida... date ghstea BoA .. 247 | — exarata ... Ad a fe: wie 280 — Smithi ... Shs fas a. ... 248 | — mitrula ... oe Bas sy ... 286 — indistineta ee tas ARE ... 250 | — harpularia ah ee a8 aou CASE — ambigua ... A660 500 EA «200)| — — Yar. rosea: 288 Haedropleura... se “i tes .. 251 | — multistriata sie ar ds abn, Poke! — septangularis ... oe ite ... 251 | — decussata yg He dine fj. 200 — — var. secalina... ee Pe ... 2538 | — — var. inflata ... Bi at ian We — rufa ag Ze re sit, ... 2538 | — — var. conoidea ye oe ... 290 — -— var. Ulideana on sae ... 254 | — Dowsoni... ea (eee aA eer wo Raphitoma ... ne ie a ... 255 | — gigantea ... a3 ee its wos PASI — harpula ... ue oe us o. 200 | — Violacea ... Sak ft se re. AGN —~ attenuata ae ate Ae ... 256 | — Odhneri ... ae - ee P88) — — var. tenuicosta on ee ... 2of | — Trevelyana — — var. gracilior A ner ... 257 | — pyramidalis — — var. notata ... ar Se ... 258 | — — var. semiplicata — plicatella sic it Bi ... 258 | — — var. leviuscula — similis ... ae os ae ... 269 | — borealis — hispidula... aE a a .. 260 | — Nordgaardi — brachystoma dm pw pw we W bo CO < © © © c oo nF GD ot bo na | — var. ventricosa on ae J 299 6 — Payraudeaui 62 | — bicarinata ne se 3 300 > bo be — tenuistriata 63 — plicitera ... a a ne eo 00) —= —— var, Carinata,.. Taranis 13, ae yas ae sos ox 64 | — Morchi ... ee or see nog OIL 64 | SUPPLEMENT - i Ey ae 303 Helix ... a me ae a: soe BOB, to A eR TS — senilis — Garlandi... — valida ee Se Ne We » Od or — Woodii ae 65 Sub-genus Macularia ... aa a 003 — Smith-Woodwardi 206.) == Orden oe con ee .... 3803 — megastoma IZ NI Cypreea ve oy Se oe .. 304 — turgida ... et 43 Ni Od Sub-genus Erosaria —... ras =n G04 Cyprea (Erosaria) spurca Columbella : Sub-genus Mitrella — — erythrostoma — — semicaudata _. — — sulcata — — suleculata = Sub-genus Columbellopsis — — Borsoni Mitra ... — ebenus — cornicula... Volutomitra ... — groenlandica Nassa ... — solida — mutabilis — — var. erthensis — Kennardi eo Sub-genus Niotha — — clathrata — — emiliana Sub-genus Hinia — — :eticulata Ar bie — — recticostata — — trivittata — — propinqua Sub-genus Telasco — — costulata : — — — var. tenuicosta ... Sub-genus Hima — — incrassata Sub-genus Amycla — — semistriata ... — — labiosa — — gigantula — — Edwardsi Desmoulea — conglobata Buccinum sae se — undatum, var. pulchra ... — — var. minima... — finmarchianum ... Purpura SYSTEMATIC INDEX. PAGE 304 306 306 306 307 307 308 309 309 | 310 310 dll 312 Purpura lapillus — — var. menapize — — var. minor — — var. ventricosa — — var. incrassata — tetragona — — var. intermedia Pisania — exigua Eupleura — caudata ... : — — var. Crowfootii Murex : — recticanalis Sub-genus Pteropurpura — — boytonensis ... Sub-genus Alipurpura ... — — elegantula | Ocinebra — erinacea ... — tortuosa ... — — var. minor — pseudo-Nystii VES RNS ot — Reedii — Canhami — craticulata — — var. reticulata Sub-genus Ocinebrina ... — — aciculata — — funiculosa Trophon Ke E Sub-genus Boreotrophon — — truncatus — — — var. major — = —— | var MLermendia’... — — clathratus — — — var. attenuata = — = var. exilis — — Gunneri ———— — var, Codd — — mediglacialis Sub-genus Trophonopsis — — muricatus = — var bel == a SS res — — — yar. cancellaia — — Bailyi ry oo Ne Oo oo 09 ae Cw OW he oo oo OD hte cr cr Ce tr Gx (Or Cro or ~ (cr cre Cr t or he > nA > wow nNnoNwe= oS OS iv) oe Trophon (Trophonopsis) Harmer ... — — hbarvicensis — — Kitchini Metzgeria — alba Searlesia — Rayni Fusus ... $4 — Rigaccii ... — imperspicuus Euthria — cornea — gracilis Troschelia — berniciensis Atractodon — elegans = — — var. inflata ... Neptunea — contraria... — — var. informis — antiqua ... bad — despecta, var. tornata ... — tenuistriata Sipho ... — torrus — gracilis — — var. convoluta — Jeffreysianus me — menapie, var. hibernica — islandicus — latericeus — pygmeus — propinquus Pleurotomide Pleurotoma — contigua ... Drilha — Jeffreys — galerita ... Clathurella — linearis — minuta Mangilia — Bertrandi — assimilis ... —- costato-striata — Gwynil SYSTEMATIC INDEX. 377 uw Gx Hw ay SJ SS) Sa © oO JI NI Co O BX o2) So © © Www w Cm @ peal fel CO bo ie.) S Raphitoma — concinnata — nevropleura — tenuistriata — mitrula ... — compacta — substriolata — nuperrima — Hornesi — consimilis — Keepingi... | Hedropleura ... — Cornishi ... | Donovania — candidissima — multilineata — lineolata Bela | — Sarsii — angulosa — borealis ... — bicarinata — elegans — multistriata — Trevelyana | Merica — contorta ... | Brocchinia | — mitreformis — — var. costata ... | Sveltia _ — Lajonkairei — varicosa ... Trigonostoma... — ampullaceum — umbilicare Sub-genus Ventrilia — — acutangulum Bonellitia — evulsa — serrata — granulata — incerta | Admete <— windula =. — — var. Couthouyi Sub-genus Babylonella ... — — subangulosa xu Admete (Babylonella) Reedi — — gracilenta a OUWert Potamides ae ee Sub-genus Ptychopotamides — — tricinctus a varenonnatal — — — yar. icenica Bittium — reticulatum — — var. trinodosa — lacteum ... — robustum — punetulum Cerithiopsis — Barleei — tubercularis — Metaxe ... — minima ... Newtoniella Sub-genus Seila ... — — trilineata Triforis R &: — perversa, var. adyersa .... Leocochlis — granosa ... Trichotropis . — borealis .,.. — Kréoyeri ... — insignis ... Torellia — vestita Aporrhais — pes-pelicani = yar, mInor — Uttingerianus SYSTEMATIC INDEX. PAGE 409 410 410 411 41] 41] 412 412 414 414 416 | 416 417 418 419 | 419 420 | 422 425 424. 4.24. 4.24. 4.25, 4.25 427 427 428 498 | 429 | 430 | 431 431 432 452 434 435 Aporrhais Serresianus — — var. Macandree Turritella — tricarinata — — var. bicincta... — communis — erosa — turris ; Sub-genus Zaria — — subangulata — — — var. mediocarinata — — decipiens Seu Sub-genus Haustator ... — — incrassata — — — var. minor — — triplicata — — vermicularis — — — var. lineolato-cincta — — erthensis — — crenulata — — marginalis — — planispira — — imbricataria — — tornata — — biplicata _... oe Sub-genus Archimediella — — bicarinata Vermetus a vs Sub-genus Petaloconcha — — intortus — — glomeratus .... Sub-genus Bivonia — — triqueter ae Sub-genus Burtinella ... — — bognoriensis EIN DUG. Norr.—The names of genera, sub-genera, species and varieties adopted in the Monograph, with the essential page-references, are printed in thick type. The Roman numeral and the following Arabic numerals in brackets indicate the plate and figures of those species and varieties which are illustrated. PAGE _Acavus hortensis —... a, et oe l6 Acroloxus lacustris (I, 18) .. ie 27, 48 Admete Couthouyi ... #7 ss .. 408 — evulsa ae ... 403 — gracilenta (XXXIX, 51, 52) s-- 410 — — milata Ber oe a mee Adil: — Reedii a a aN ... 409 — serrata oe ncn ie ... 404 — subangulosa te 2 ... 409 — undato-costata os ... 408 — viridula (XXXIX, 42— 47) ... 406 — — var. abnormis ... 408 = — var. Couthouyi (XXXIX, 48, 49)... did Sx, AOE — — var. producta .... a 406 — — var. undato-costata ... 408 | — Wouweril (XXXIX, 50) ... .. 410 Alectrion trivittata ... ‘er sce Oye Alipurpura (s.-g.) slegantuln xe .. 9340 Amblyacrum (s.-g.) harpula a .. 205 Amycla (s.-g.), see Nassa_ ... am me 828 — rosacea ae Bae a Bee Anachis (s.-g.) suleata ah nog I = (s.-g.) suleulata ... ae Py eo 0Se! Ancilla Nysti (XII, 32, 33) aoe eee, Anceillaria obsoleta ... ve ee 55g. OP Ancylus lacustris... oe ee WG Anomalosipho Actoni (Xv, 12 ) pees seg. LOS -- altus (XV, 6) af 150, 152 —_ -—— var. costellata (XV, 11) 151 _— — var. virgata (XV, 7-9) 151 PAGE Anomalosipho Bellii (XV, 13) 151 _ Verkriizeni ... ¥ 149 — _ var. _ plicifera (XV, 10) 149 Aporrhais Macandrez 437 — pes-carbonis 437 —= pes-graculi 435 — pes-pelicani (XLI, 26- 29) 432 — — var.minor(XLI,30) 434 — — var. Serresianus ... 406 — Serresianus (XLI, 33) ... 436 = — var. Macandree (XLI, 34) 437 — speciosa 434 — Uttingerianus (XDI, 31, 32) 435 Area diluvii ... 5 Archimediella (s.-¢ ‘| ramets 456 Astyris rosacea (XIII, 13, 14) 57 -—- (s.-g.) Holbolhi 57 — (s.-g.) sulculata 308 Atilia Borsoni ~ al Atractodon elegans (XXXVI, 9) 115, 364 — — var. inflata (XXX VII, 10-13) 365 Babylonella (s.-g.) gracilenta 410 — (s.-g.) Reedii 409 — (s.-g.) subangulosa 409 ae (s.-g.) Wouweri 410 | Bela zequalis ... 300 4.66 Buccinum propinquum prysmathicum pyramidale reticosum ... reticulatum rosaceum ... rugosum ... Sabinii, Gray scalariforme scriptum ... semistriatum sericatum serratum ... spectabile.. striatum ... suleatum ... tenebrosum var. Boreas tenerum tenue (VIII, 10, ID terre nove (IX, 11, 12) 90, 100, 109, 114 tetragonum Tottenii (X, 6) — var. islandica (X, tritonium truncatum tumidulum turonense... undatum ... — var.acuminata(VI,3,4) 95 = var. borealis — var. clathrata (VI, i, 2) 90 | — var. coerulea (VII, 3, 4) — var. crassa (VII, 1, 2) 94 _— var. flexuosa (VI, 5) ... — var. groenlandicum — var. leviusculum — var. littoralis (VI, 9, 10) == var. Maxima — var. minima (VII, 6) 97, 334 — var. pulchra (X, 13) ... BE IGG, Ss LL 17,18) 38s — var. pumilio — var. Schneideri (VIII, 1, 2) — var, striata (VI, 6, 7) 91 | INDEX. PAGE PAGE 73 | Buecinum undatum, var. tenera (VI, 8) 92 65 — — var. zetlandica (VII, 5) 94 295 -— undulatum ee OG oll — variabile (X, 4, 5) 108, 321 318, 320 — ventricosum 105, 109 57 | Bulimus lubricus = 18 .. 61 | Burtinella (s. 8) homnorionats 461 179, 183 104 | Cancellaria acutangula 401 te UDO == ampullacea 399 72, 328 _- arctica ... 429 99 — Bellardi ... 402, 404 70 — buceinoides 407 85 — contorta ... 394 91 -- coronata 397 307 — costellifera 406 100 — Couthouy 407 92 — elongata 405 104 — evulsa 4.02 —- gracilenta 410 — granulata 405 116 — Jonkairiana 397 106, 109, 113 | — Lajonkairei se A 7,0) — i114 — minuta ... 406, 409 328 —_ mitreformis 396 129 — Nysti 409 103 a occulta ... 409 Ar OD _ pusilla 396, 409 90, 94, 108 — scalaroides 397 — serrata ... 404 94, = subangulosa 409 — umbilicaris 400 — varicosa ... 397, 398 91, 97 — — var. simplicior... 398 — viridula ... 406 93 | Cardium casertanum... 44 98 — edule 413 92 | Carychium exiguun ... ; ss 28 — minimum (I, 12) 24, 48 93, 333 = ovatum (I, 11) ... 25, 48 94 — pachychilus 25 Cassidaria bicatenata ie He shoe plist) 96 | = — var’ Canhami (II, 14) 59 —- — var. rugosa... 58 96 — tyrrhena (II, 13) 58 Cassidea saburon 59 96 | Cassideum (s.-¢.) 58 Cassis saburon 59 INDEX. PAGE Cerithiella trilineata ... 424 Cerithiolum lacteum ... 416 — reticulatum er 415 Cerithiopsis Barleei (XLI, 14, 15) 419 — lactea ae a 416 — Metaxe (XLI, 16-19) 422 — metula ... 6 420 — minima (X LI, 22) 423 — — var. nana, Jeffreys 4.24. — — var. ovoides (XLI, 23) 423 _- trilineata a 424 — tubercularis (X LI, 20, 21) 420 = — var. Barleei 419 = — var. minima 423 = — var. hana 423 Cerithium adversum ... 425 — conecatenata 424, — Crosseanum 422 — elegans 416 — granosum 427 — Henckeliusii 421 — lacteum 416 — Lamarckii 413 —_ metaxa 422 — minimum ... 423 — perversum ae 425 ae — var. Belli 425 — pseudo-reticulatum ... 416 a punctatum A411, 412, 419 = punctulum 418 = reticulatum ee 414, -- — var. punctulum 418 = = var. trinodosa 416 — sinistratum .. 427 = tricinctum a ae 123, 411 — — var. inornata ... 412 — trilineatum 424, = tuberculare 420 == — var, nana 423 — — var. subulata 419 = variculosum 418 Chrysodomus antiquus i 808 = contrarius 5, 60, 156 despecta, var. carinata 162 — elegans : . 864 — intersculptus ... 157, 166 — sitkensis 138 _— tornatus 369 Chrysodomus Turtoni Cinctella (s.-g.) trilineata Cirillia (s.-g.) linearis Chenopus anglicus — pes-graculi = pes-pelicani var. anglica ... == Serresianus — Uttingeri ... = Uttingerianus us: Clathurella concinna (XXVIII, 22, 23) Cordieri (XXVIII, 30, 31) emarginata hystrix (XXVIII, 24, 25) inflata oo oS Leufroyi (XXVIII, 13-15) linearis (X X VIII, 26, 27) —- (XXXIX, 34) = —- var. equalis (XXX, var. intermedia COOV TIT minuta (XX XIX, 33)... purpurea (XXVIII, 16, 17) var. Minor (XX V 18, 19) var. Philberti (Cordieri) reticulata volutella Clausilia pliocena Clavatula brachystoma cancellata .. a concinnata costata ee aus interrupta (XX VI, 20) Jouanneti — levigata — linearis — mitrula — perpulchra Philberti ... plicifera. — Trevelliana Clinurella (s.-g.) Borsoni Cochliocopa lubrica ... Columbella abbreviata ‘ie Borsoni (X XXIII, 20, 21) var. pallida (XX VIIT, 29) Philberti (XXVIII, 20, 21) ... 233, 39) 28) 234 231, 234 TI, 234 234 239 . 248 21, 47, 48 261 239 382 244 210 203 263 243 269 238 oe Pe 266, 300 294 309 18, 48 307 309 468 INDEX. PAGE PAGE Columbella compta ... 56 | Cyrena trigonula 39 — erythrostoma (XXXII, me 12) 306 | Cyrillia (s.-g.) linearis concinna 236 — Holboélln ... 58 = minor 310 | Daphnella attenuata 256 — rosacea 57 — gracilis 241 — scripta (II, 8, 9) ree eas, os hispidula ... 260 -— semicaudata (XXXIIT, 9,10)... 307 | — Morchii 301 _— subulata (II, 11, 12) 56 — nevropleura 383 -- suffusa 309 -— stria 243 — suleata (XXXII, 14, 15) 307 _- volutella . 243 — -— var. abbreviata (XX XIII, Defrancia cylindracea 292 MED) 9 ec 56 se0S — elegans 393 — —- var. elongata (XXXIII, — exarata 285 16, 17) 308 — gracilis 24] -= suleulata (XX XIII, 18, 19) 308 — hystrix 240 Columbellopsis (s.-g.) Borsoni 309 = Leufroyi ... a a Colus pygmzus : 374 — linearis 257, 379 Cominella (s.-g.) aquitanicum 316 a — var. equalis 238 Conopleura crassa 224. _ nobilis 281 — elegans ... 222 = purpurea ... 2 232 — Maravignie 222 — — var. Philberti ... 234 — sigmoidea 225 reticulata ... 239 Contortia (s.-g.) contorta 395 — scalaris 278 Corallinia (s.-g.) aciculatus 347 — stria 243 Corbicula fluminalis 36, 39, 47, 48 — Vahhi 296 Cordieri (s.-g.) hystrix 240, — violacéa 292 — reticulata 239 - viridula 289 Crassispira (s.-g.) Brocchii ... 220 volutella .. 242 Crassopleura Maravignee 222 | Desmoulea conglobata (XXXIV, 27) 89, 333 Cyclas amnica 43 | Dofania (s.-g.) triqueter 460 —— appendiculata 47 Donovania candidissima (XXXIX, 39) 389 — cornea : 42 — lineolata (XXXIX, 37) 390 Cyclostoma elegans ... ee 20 — minima 390 Cymatosyrinx (s.-g.) incrassata 222, 223 — multilineata (XXXIX, +38) 389 — sigmoidea, 226 | Drillia Brocchii (X XVII, 20, 21) ... 219 Cyprea affinis 50 — crassa ox oath hee — europea 49 — crispata (XXVI, 99, | 28) ad 217, 226 a — var. affinis ... 50 = — var. papillosa 227 — lurida a 304 — emendata (XXX, 40) eee. — pediculus var. europea 49 — galerita (XXXIX, 36) 228, 378 — pisolina OM LC ENOLUMIN(GXOXO\ Alea Gamlizajieg 220, 228 — pyrum 304 ~ — var. elongata (XXVII,18) 221 -—— sphericulata = 49 ~ var. speciosa (XX VII,19) 222 — (Erosaria) spurea (XXXII, 7,8) 304) — imcrassata (XXVIII, 28) 222, 225 Cyprina islandica 60 | — var. crassa (X XVII, 32) 224 Cyrena consobrina 39 | = — var. dertomagna (X XVII, — Duchastellii ... 39 29) = 223 Gemmellarii ... var.miominor (XXVIL, 30) 223 Fusus alveolatus PAGE Drillia incrassata, var. Nysti (XXVII, 31) 224 Jeffreysii (XX XIX, 35) 377 = Kendalli (XX VIII, 2) 229 == Loprestiana 219 = modiola 230 —- semicolon x ee 377 — sigmoidea (X XVII, 24, 25) 225 — -—— var. pliomagna (XXVIII, = 26) 226 — terebra (X XVII, 33) 229 Drilliola (s.-g.) emendata 227 — Erosaria (s.-g.) spurca .. 804) — Eulota fruticum (1, 1) .. 9, 48 — Eupleura caudata (XXXV, 24) 337 — — var.Crowfootii (XX XV, 25) 338 _— Euthria cornea (XX XVII, 7, 8) 361 — — var. minor ... 362 — gracilis (XX XVII, 6) 362 — minor 363 — Fluminina (s.-g.) astartoides 43 — Fossarina (s.-g.) Henslowanum 46 — rs .. 146 = antiquus 156, 165, 365, 368 = — var. behringiana 164. = — var. brevispira 164} — — var. striata ... 169 == attenuatus 192 — Banffius 350, = berniciensis 363 == buceinatus son LNG — carinatus 156, 163 castaneus, Sow. 172 == — Brown soo | US) = cinereus 126, 141 = clathratus 127 = comptus OO — contrarius 156, 366 = cordatus pool lteks - corneus 178, 361 = —- var. minor 362 —- costatus 136 — — var. rugosus e. san dats — curtus ... 176, 178, 180, 375 — decemcostatus... 157, 161, 163 — deformis a — despectus 156, 16( -- INDEX. Fusus Deshayesii ebur echinatus elegans Fabriciu fenestratus Forbesi.. fornicatus glaber gracilis a — var, convoluta harpularius hirsutus imperspicuus (XXX VII, incisus ... isJandicus — var. pygmea Jeffreysianus Kroyer lamellosus, Boren (XIV, Gray Phil. Largillerti latericeus lavatus : longiroster, ae (XIV, longirostris, Hornes Menapii modiolus norvegicus Olavii ... peruvianus pleurotomarius propinquus pygmeeus : Rigaccii (X XXVIII, 16) Rosenbergi Sabini, Hancock — Jeffreys Sars ee ; sealariformis, Gould ... sinistrorsus sitchense spitzbergensis ... striatus, Sow. ... — Reeve togatus tornatus 4.69 PAGE 361 iO 131 864 131, 356 136 122, 140, 144, 146 166 a ale Ss 175, 178, 192, 372 178 287 201 360 Sep ae alta 136, 175, 187, 373 374 196 136, 148 174 127 175 152 189, 374 wan OME 123, 173 174 186 230 154 176, 193 302 254, 295 195, 375 374 360 146 183 375 198 Aol 156, 159 137 136, 167 ... 164 176, 369 ae soa LS) 157, 163, 369 17, 18) 24) 23) 470 INDEX. PAGE Fusus tortuosus i 190 | Helix Ogdeni (XX XIII, 1)... cs — var. attenuata 191 — pulchella — turricula ... 278 | — _ putris == braver... 152, 154 hice rubiginosa — ventricosus, Gray 171,370 | — rysa at #3 _ a Sow. Sa es sericea, var. rubiginosa — Waelii (XLIV, 22) 359 — gsuttonensis — tentaculata ai Genotia ornata 216 — (Vallonia) tenuilimbata — pannus ff ¥ 215 | Hemipleurotoma (s -g.) contigua — ramosa (XXVI, 21, 22) 211 | = denticula ... Ginnania (s.-g.) brachystomum 261 — plebeia a nebula 272 | Hima (s.-g.), see Nassa — — ginnanianum 273 | Hinia (s.-g.), see Nassa — — levigatum... 275 | Homotoma elegans Gulia (s.-g.) acutangula 402 ~~ emendatum — hystrix Hedropleura Cornishii 388 | -— Leufroyi ... — rufa (XXIX, 7, 8) 253 — Philberti... — — var. Ulideana (XXIX, | — purpurea... 25 NO) 22 254 | — stria — secalina z= se ... 253 | Hydrobia obtusa — septangularis (XXVII, 27; Hygromia hispida os XXIX, 3, 4) 261 a8 incarnata (I, 6, 7 == — var. secalina — rubiginosa (I, 8) (XXIX, 5,6) 253 | Haustator (s.-g.), see Turritella . 446 Inobittium lacteum ... Helicigona arbustorum 14, 48 | Iphinoe (s.-g.) Kroyeri — — var. alpestris . 14 | Isocardia cor ... Helicodonta lens (I, 5) 18, 47, 48 Helix arbustorum 14,17 | Jaminia cylindracea (I, 10) — auricularia 31 — muscorum ... — cornea 32 | Janulus (s.-g.) rysa — faux-nigra 14 | Jumala Turtoni — fruticum 9 — globularis, var. rubiginosa 11 | Lachesis candidissima —— Hesendonckii ... 15 — magna — hispida i 10, 23 | — multilineata “fe — hortensis (I, 4) 16,48 Leocochlis granosa (XLI, 11-15)... — incarnata eat lt) al — var. Macandrewee — lactea (I, 2) 14, 47, 48 = var, pommeraniz — lens 13 Lampusia (Triton) — lenta 38 | Lathyrus albellus — lubrica ... 18 Latirus albus... — muscorum - * ae Re ee, | — costifer — nemoralis (I, 3) 15,48 | — gibbulus — var. hortensis 16 | Leufroyia (s.-g.) concinna ... — Oberndoerferi ... 304 | — Leufroyi see Ok 10, 48 11, 47, 48 11, 48 429 5, 205, 421, 439 20, 48 19, 48 8 155 INDEX. PAGE Limnea auricularia ... a P52 roll — — var. acuta oe 31, 48 — butleyensis ... : 28, 31, 47, 48 — Harmeri(I,14) _... ... 29, 47, 48 — Holbolli ... a8 Re oe oS ==) labio + 5 oh: Sen — limosa ae Sa AA shoe. veh) — palustris ... A = 28, 48 — pereger ae hes . 30, 48 | — + Pmgelln ... rE ae sao S| tenuis fa: a pie ee 30 == haben, _. : ae 28, 31 — Woodi ne 30, 47, 48 Limnezus acutus Bok i SAP) Lol Liomesus canaliculatus (XII, 1, 2) alo, Lithoglyphus fuscus (I, 16) cap 34, 48 = naticoides eA at ab5 OO) Macularia (s.-g.) Oberndoerferi... B04, — Ogdeni... ee 303 Mangilia albida (X XIX, 12) ae 247 — — var. cerulans .. 246 | — ambigua (XXIX, 17, 18) ... 200 a anegusta ... = Poke @ Glee _ assimilis (XXXIX, 20) sao Gheill — attenuata ... Sf son PAS — Bertrandi (XXXIX, 21-23) 266, 380 — — var. cerulans ... ... 246 _ — var. elongatula Brae piel) _ brachystoma re noe, YAOI — cerulans (XXIX, 15, 16). ... 246 — Cornishii ... ae ... 9388 — costata (XXIX, 13) oe 244 — — var. coarctata (X XIX, 14) 245 —- costato-striata (XX XIX, 18,19) 381 — dubia (X XIX, 11) nae .. 246 — elegans... ies she bea) = exarata ... a ae ... 285 _- ginnania ... 3 Ne =a 208) — gracilis). bot . 241 _ Gwynii (XXXIX, ‘ 24) aoe 382 — hispidula ... oe aes ... 260 — Holbolli ... see ee OG — indistincta (X XIX, 19, 20) ... 2650 _— Leufroyi ... Se ... 285 ~ linearis 537 -- nebula Bi aor #8 bee — — var. ginnaniana ... 273 | Mangilia nebula, var. levigata = purpurea ... — rufa aa — — var. Ulideana ao septangularis — §mithii (XXTIX, 21, 22 — striolata, Risso — — Scaechi — Trevelliana — turricula == violacea Melampus pyramidalis Merica contorta (XL, 5-7)... — mitreformis | Metaxia (s.-g.) Metaxa nace Bie Meyeria alba (XIII, 15, 16) — albella — pusilla Mitra cornea ... — cornicula (XXXIIL, 2 2, 3) — ebenus (XXXIII, 4) .. — grenlandica — lutescens Mitrella erythrostoma — scripta — semicaudata — suleata sti _ — var. abbreviata — — var. elongata Modiola modiolus Monacha (s.-g.) incarnata Monophorus (s.-g.) perversus Murex aciculatus — adversus — alveolatus sei _- _- var. angulatus — — var. consocialis — antiquus — attenuatus — Bamffius — barvicensis — borealis a : — boytonensis (XXXV, 21) — Canhami =—— carinatus — clathratus — contiguus 13 135, © 116, 5,3 135, ; Murex contrarius INDEX. PAGE 156 corallinus 347 corneus, Linn. 180, 361 — Penn. 175 costatus 24.4, costellifer ci ... 406 craticulatus 1381, 346, 348 Crowfootil 338 despectus fee UG) echinatus 131, 239 elegans 237 (Alipurpura) Slecantale (XXXV, 20) 340 emarginatus ... a ... 242 erinaceus 124, 341, 342 exiguus 336 funiculosus 348 gracilis 24] harpula ’ 255 heptagonus 120 incrassatus 117 insculptus, A. Bell 336 — Bellardi ... 337 interruptus 210 intortus 212 linearis 237 longiroster 173 metaxee 422 nebula 272 INVSbl os 344 oblongus 219 peruvianus 351 pseudo-Nysti... 343 purpureus 251 recticanalis 339 Reedii.. 344 rudis (XII, 3- 5) 122 rufus = 409 rugosus 11835), 11337 scriptus 55 septangularis... 251 striatus 164 subantiquatus 163 subulatus eae OO tortuosus 125, 342 tricinctus 411 tristichus 341 tubercularis 420 turricula, Broce. 203 PAGE Murex turricula, Mont. 276 Muricanthus (s.-g.) ... 5a _ woo Muricopsis (s.-g.) exiguus ... 336 Nassa Caronis 316 —— ¢rassilabris) os: i Oh — elegantula ... 6 i : 84 — Kennardi(V,11)... ee ex 16% — — CXERIOV ; 4: lee. Be. 316 — — var. elongata (V, 12, 13)... 87 — mutabilis (XX XIII, 23-25) 64, 314 — — var. Companyoi ... 314 _ -- var. erthensis ( XXXII, 26) at . 816 — —: var. inflata it fet colo — — var. pliomagna ... . 316 — os var. St. Erthensis 2. *oh6 — solida (XXXITI, 22) = ~. Sls — (Amycla) Edwardsi (V, 22,23) ... 86 — (XXXIV, 15) 329, 332 gigantula (XXXIV, 22, 23) 331 Hoernesi_... a Aon era italica ae ae .. «3829 labiosa (XXXIV, 20, 21) 72,330 semistriata (XXXIV, 24) 328, 332 — var. calabriensis 331 — var. Edwardsi 332 — — var. labiosa ... 330 — totistriata : 331 (Desmoulea) conglobata (XXIV, 27) 89, 333 (Hima) angulata, Brocch. ... ce SU = — S. V. Wood 550 ted) — consociata (IV, 17, 18) 75, oe — var. belgica (IV, 18) 7 -- var. brevis (XIIT, a 76, 123 costellata ... 55 in) Woe Cuvieri a i 81, 321 Dautzenbergi (V, 5) 63, 78 = var. crassisculpta (V, 6) Bet tO = var. minuscula (V, 8) Seaets:) — var. simplex (V, 7) Be ied *) Dollfusii (V, 9) eae 80 — var. convexa (V, 10) 81 INDEX. 473 PAGE | PAGE Nassa (Hima) elegans, J. Sow. (IV, 19) Nassa (Niotha) Cantrainei (III, 9, 10) 68 76, 123, 326 = — clathrata (III, 3) .. ; 66 = — var. intermedia ca a Ta = (XXXII, 28- 30) 317 (IV, 20) ... "7 — — — var. ficaratiensis 317 granifera 85, 328 = == emiliana (IV, 5, 6) 67 — granulata (V, 1), 77, 89, 326 a | dee — 0:2:0.4 715) 317 = abe var. elongata (V,2) 78 = = ligustica (III, 7, 8) 71, 318 == — var. fenestrata (V,4) 78 = as Michelottiana vost OG = -- var. gracilis (V, 3; aa = serrata (III, 5, 6) 64, 70 XIII, 20) ii — (Telasco) costulata, var. tenuicostata — inerassata (XXXIV, 8-10) (XXXIV, 25, 26) ... 323 80, 88, 324 — (Uzita) aubigniensis ... . 62 = — var. 2 (V, 25, 26) = — limata (IV, 1, 2) 66, 69 6873967) — — var. anomala (IV, 3) 70 == dim ... st a ae De — microstoma (LV, 4) ... Go — Kermodei (XIII, 17) 74, 123 = — prismatica (III, 1, 2) 65, 69 — limatula (IV, 9, 10) vis — prysmathica ... 65 — monensis, Forbes (IV,7,8)... 74 | — — reticosa ae =, 0 — monensis, S. V. Wood 7: | = — var. cancellata (III, — musiva 84. | 19) 63 — Perrierize Bey — — var. concinna 63 — pumila (V, 24) a — var. costata (III, 15, 16) — pusillina (V, 27, 28) 81, 223 | 63, 123 — — var. variabilis | fa os — var. elongata 62 — pusio.. a isi | —_ — — var. incisa (III, 4)... 64 — pygmea a (XXXIV, 6,7) 88, 326 = = — var. lineata (III, 17, 18) — spectabilis (V, 16, 17) 69, 85 | 63, 123 — turonica (V, 14, 15)... by ae — var. pulehra(III,14) 68 _ a OSESXEY, 11-14):896, 998), > — var. simplex 63 — variabilis Sl, Bs | — _— — Vee pe 64 — _varicosa 327 = — semireticosa (III, 11) 64 — venusta (V, 18) g2) — — = var. minor (III, — — var. Woodii (V, 19)... 83 12, 13) 65 — Woodwardi (V, 20, 21; Neptunea antiqua (XIX, 1) 158, 168, 170 eS) = 83 — — (XXXVI, 26) 368 (Hinia) lamellilabra av, Le 13) 83 — — var. brevispira ... 164 == -- var. elegantula — — var. Browni 169 (IV, 14-16)... 84 — — var. carinata 162 — musiva 84, | - — var. despecta 160 — nitida : 320 — — var. gracilis eee O — propinqua (XXXIV, ‘18, 19) — — var. icenica (XIX,11)... 170 73, 89, 322 — — var. inversa (XXXVI, — pulchella 84, 27, 28) 368 — recticostata (XX XIII, 27) 83, 320 a — var. striata (XIX, 7- -10) 169 — reticulata (XXXIV,1,2) ... 318 | = — _var. subantiquata 163 a _ var. nitida | = — var. subtornata(XIX,2,3) 169 (XXXIV, 3-5) 319 | _ — var. tornata 369 | attenuata ... 191 trivittata (XXXIV, 16,17) 73, 321 | 4. Neptunea berniciensis + INDEX. PAGE : 363 castanea (XVIII, 7) ae he contraria (XVI, 1, 2) 156, 159, 186 — (XXXVII, 3)... 366 — var. angulata (XVI, 7) 160 — var. carinata (XVI, 5) 160 — — (XXXVII, 45). TOT — var. informis (XVI, 6) 160 — — (XXXVI, 30,31) 367 — _ var. sinistrorsa (X VI, 3, 4) | 157, 159 | curta 180 decemecostata Webs} deformis ... ae 160, 368 despecta (XVII, 1) 155, 158, 160, 167, 170 var. behringiana (X VII,8) 164 var. carinata (XVII, 5; XXV, 4) 162 — var. Cobboldiw (XVIII, Sh, BD) sac 164 var. curtispira(X VIII,6) 167 var. decemcostata (X VIT, 3,4; XXYV, 3, 5) var. intermedia (X VII, 2) 165, 171 — var. intersculpta (X VIII, DI EXONG VE l!))inee 161 166 var. subantiquata (X VII, oe Aap. O51) 163 — _ var. subspitzbergensis (XIX, 4-6) 167 var. tornata (XXXVI, 29) 369 ebur me 197 fornicata, var. multistriata 166 glabra ae OS gracilis 175, 177, 372 IS Ubae eee re: 201 ignota (XXIV, 16) 173 incisus 138 | intersculpta 171 islandica ... 187, 373 Jeffreysiana 196, 373 Kroyeri 148 Largillierti 153 var. pumilio (XVIII,1,2) 165 | _ Neptunea latericea norvegica ... — pertenuis ... — _ propinqua... — pupoidea .. — Sarsil — _ sinistrorsa spitzbergensis ane — tenuistriata (XX XVII, 1, 2) — togata tornata torra tortuosa turrita Turtoni undulata ... varicosa a Lae ventricosa (XXIII, 20) ... Verkriizeni — virgata Nerita piscinalis Nesza candidissima ... lineolata ee = Newtoniella trilineata (XLI, 24) .. Niotha (s.-g.) Nucula Cobboldize Ocinebra aciculata (XX XV, 18, 19) Canhawi (XXXV, 15, 16) craticulata (XXXVI, 17-19) var. reticulata PAGE 189, 195, (XXXVI, 20. 21) erinacea (XII, 12-14) (XXXV, 17) funiculosa (XXXVI, 1, 2) pseudo-Nysti (XX XV, 12) 13) Reedii (XX XV, 11) _- tortuosa (XX XV, 7, 8) 1D): eee: Ocinebrina (s.-g.) aciculata —- funiculosa var. similis (XXXV, 125, 342, : var. boytonensis (XII, 8) var. clathrata (XXXV, -—— var. minor (XII, 9-11) 123, 374 154 374 375 186 198 , 159 167 369 181 170 Oligotoma Basteroti . — fammnetala (XXVIL 12- rie XXVIII, 5-8) var. proxima (XXVIII, 3, 4) _- decorata (X XVII, 3, 4) — festiva (XX VII, 5-7) ... — ornata (X XVII, 1, 2) -- pannus (XX VII, 8-11)... Paludestrina Reevei Paludina fusca — glacialis — lenta = media — obsoleta — parilis — tentaculata... — _vivipara Panopzea Menardi Parasipho Kroyeri (XV, 4, 5) — var. major = — var. pumila Patella lacustris Patula rysa : Pera appendiculata ... Peratotoma concinna — harpula a hystrix ... — Leufroyi = linearis ... — purpurea — reticulata Petaloconcha (s.-g.) Slomeruens — intortus Philbertia (s.-g.) purpurea ... — Philberti .. Pisania exigua (XXXV, 22, 23 ; XLIV, 19) Pisidium amnicum (I, 21) var. sulcata -- astartoides (I, 23)... — casertanum (I, 19) —- concentricum — fontinale vy — -- var. ee ae — Henslowanum (I, 22 var. supinum — obliquum ... INDEX. 47 5 PAGE PAGE 215 | Pisidium pusillum 44. — suilla 45 % 46 218 — (Rivulina) supinum y | ey 20) 45, 48 Planaxis mammillata 319 219 | Planorbis clathratus 32 217 — complanatus 3 216, 227 — corneus 32, 48 216 — marginatus PS 215 — precursor... ..88, 48 — spirorbis ... ..82, 48 34, 48 — umbilicatus 34. 34 | Pleurotoma albidum 247 36 — ambiguum 250 By — antwerpiensis 205 ou — arctica 291 37 — attenuata 256 37 — a var. gracilior 257 35 -— — var. notata ... 258 38 — — var. tenuicosta 257 92, 211 — — var. volvula ... sun OY 148 —_ Bertrandi 266, 273, 380 149 — bicarinata 299, 3938 149 — — var. violacea... 292 27 — bipunctula 218 8 — Boothii ... 235 46 — borealis ... 298 236 = brachystoma 261 255 — Brocchu on El) 24.0, — carinatum 230, 299 235 — castanea 379 237 — cirratum 302 232 _- coarctata 245 239 — ccerulans 246 459 _ compacta 385 457. — concinna ee 230) 232 = concinnata : 261, 382 234 -~ contigua (XX XIX, l, : 2) 205, 377 336 — Cordier ... 239 .. 42, 48 — Cornishii 388 Sao AS — coronata Be col 43, 48 = costata ... : 244, 269 .. 44, 48 — — var. coarctata 245 44, —— costato-striata ... 381 45 = crassa w. 224 ; 46 — erispata ... 217, 226 .. 46, 48 — — var. papillosa .. 227 45 — crispatum, Phil. 219 42 — — Reeve 219 476 Pleurotoma curtistoma PAGE 27 decorata x oY jon PAL) decussata, 261, 289, 300, 382, 386 denticula 208, 209, 221 denticulata (X XVI, 7, 8) 208 Dowsoni . 291 elegans, MOll. ... 393 —= IBouill. 222 emarginata 241 emendata 22 exarata ... 285 TESiiviel wees , seen DiS galerita ... Ses si 228, 377 Gastaldii (X XVI, 19)... 209 ginnania 273 ginnanianum seo) EBIe| gracile 241, 256 gracilior 257 granulina 217 Gwynii ... 382 harpula ... 2565 harpularia 287 Heckeli ... is Pee malt hispidula 259, 261, 383 Hoernesi 387 Hosiusi 221 hystrixe 2: 240 icenorum ..- 220 incrassata ... ua: 222, 224 inermis (XXVI, 5) _... een, — var. nuda (XXVI,6)..._ 207 inflata 235 interrupta 210 GORA 212 Keepingi 388 levigata 274 Leufroyi su BD linearis . ne 237, 379 Loprestianum ... 219 Maravigne 222 megastomum 267 mitrula ... 385 modiola ... 230 Morchi ... 302 Morreni 212 multistriata 288 nana, Scacc. 268 nanum, Phil. 268 INDEX. Pleurotoma nebula — var. elongata nebulosa neuropleurum .. nivale notata ornata pannus ... Payraudeaui Payraudoti perpulchra Philberti plebeia (X XVI, 9, 10) plicatella porrecta purpureum pyramidalis ramosa ... Renieri ... a reticulata, Brown — Phil. robusta ... Rochettz rufa apt — var. Ulideana scalaris ... : — var. abyssicola — var. ecarinata ... scalaroides secalinum Selysii (X XVI, 17, 18) semicolon semiplicatum = var. minus senilis septangularis sigmoidea similis Smithi ... stria striolata subulata Suessi Tarentini tenuistriata terebra ... Trevellianum Trevelyana 215, 216, 2 218, 2: 259, 248, 270, oo gc Ns % ; S ib boob tS hw Ww Q Gop st C€ ¢ eo oO © To) nse INDEX. 477 PAGE PAGE Pleurotoma turgida iv 267, 269 | Purpura lapillus (XI, 11, 12) 6, 117, 334 as turricula, Broce. (X XVI, 1, 2) — — var. angulata 165 203, 205 —_ — var. angusta (XI, 19) 117 — — var. antwerpiensis — -— var. brevis (XI, 5) 117 (XXVI, 3, 4) 205 — a - (XXXIV, 32) 3385 — _ Mont. 276 - — var. butleyensis (XI, 20) 118 — = var. scalaris 278 — — — (XXXIV, = = var. rosea 288 31) 335 — turrifera Af ... 208 = — var. carinata (XI,4) 117, 336 — Ulideana ie . 254 — — var. connectens (XI,2) ... 118 — variegatum a i .. 234 — — var. crispata 117 _- Vauquelini 247 — — var. elongata (XI, 14) 117 — violacea ae ves «92 = — var. imbricata (XI, 3,9) 117, 336 — — var. gigantea ... 291 -- — _ var. incrassata (XI, 1) 117 — volutella Br “ah 242 -- — — (XXXV,1) 335 — volvula 257 — — var. major . 117 Plicifusus (s.-g.) Herendeenii 184 — — var. menapie (XXXIV, — Kroyeri 136 29, 30) . . 834 = spitzbergensis 136 = — var. minor (XXXIV, 33) Polytropa lapillus 117 117, 335 = — var. imbricata » Wily _ — var. newbourniensis (Xi, Pomatias elegans... ' Ure pee aat0) Loy aee:. 118 — Harmeri (I, 9) 26, 47, 48 — — var. oakleyensis (XI, 7, 8, Potamides tricinctus (XL, 23-25)... 411, 448 10,15). 118 = — var. icenica (XL, 26) —_ — _-var. ventricosa ( XXXIV, 412, 419 34) a tnd .. 835 _ — _var. inornata (XL,22) 412 — — var. vulgaris (XI, 21-23) 118 a= — _ var. subagranosa 412 — tetragona (XI, 6) .. ; 116 Pseudotoma intorta (X XVI, 11-14) 212 — — var. Sree (XI, 18, 18) 116 — — var. Morreni (XXVI, — — var. intermedia (XXXIV, 15, 16) 213 28) ... 336 Pteronotus (s.-g.) 340 | Pyramidula bifrons ... ar aoe 2 Pteropurpura (s.-g.) ae 339 — rufescens a ; ane 8 — triformis 341 — rysa a 8, 47, 48 Ptychopotamides (s.-g.) eictaae: 411 = suttonensis Kise 9, 47, 48 — — var. sub- Pyrene rosacea “f ee Sy agranosa 412 | Pyrolofusus (s.-g.) daformist 160, 368 Pupa cylindracea oe — edentula a 7 | Ranella caudata 337 — marginata , Ree soa) — pygmea 326 — muscorum 19, 23 | Raphitoma ambigua... ! 250 — umbilicata ee ee ee = 20) — attenuata (XXX, 8, 9) 256, 258 Purpura cingulata se 120 = — _-var. gracilior (XXX, — derivata (XII, 30) 119 12) . 257 — exilis 119 os _— var. notata (XXX, 13) 258 — hemastoma... 119 = _ var. Payraudeauti ... 262 — incrassata (XI, 1) 117 -- — var. tenuicosta (XXX, — ~- (XXXV, 1) 335 10, 11) 257 478 INDEX. PAGE PAGE Raphitoma attenuata, var. volvula.. ... 257 | Raphitoma tenuistriata, var. carinata -— brachystoma (XXX, 30,31) ... 261 | (XXIX, 33) 264 — compacta (XX XIX, 7) 385 — turgida (X XIX, 30) 267 — concinnata (XX XIX, 3, 4) 382 — valida (XXX, 22, 23) ... 265 — consimilis (XX XIX, 9) 387 — volvula ... ae soe, — costata .. 244 — Woodii (XXX, 5) 265 — costulatum striolatum ... 248, 270 | Recluzia aperta 431 —- curtistoma (XXX, 27-29) 271 | Rimella (s.-g.) gracilenta 60 — decussata : 386 | Rivulina (s.-g.) supinum 45 — Garlandi (XXX, 4) ) 264 Rostellaria gracilenta (II, 3) 60 — ginnanianum 273 — pes-pelicani 432 — gracilior ... 258 — serresiana 436 — harpula (XXX, 1, 2) 255 _— Uttingerianus 435 — hispidula (X XIX, 27) .. 260 — — var. pliocostatissima 260 | Searlesia alveolata ... Be Loo» ASG = Hoernesi (XX XIX, 8)... 387 — Bjornsoni (XIV, 6- 9) .139, 141, 143 —- hystrix 240 — consocialis .. 147 — incrassata “ 223 — costifer (XIII, is) 136 = Keepingi (XXXIX, 17), 388 a= — var. cancellata (XIII, 4) 138 = levigata (XXX, 35, 37) 274 _ — var. crassa (XIII, 11) ... 189 ps — )COXXIX, 17) 384 | = —— var. elongata (XIII, 5)... 138 a — var. minor (XXX, 36) 276 a= — var. islandica (XIII, 7-10) 189 — megastoma (X XIX, 36, 37) 267 = — var. monensis (XIII, 6) 123, 140 == mitrula (XXIX, 23-25) 269 = — var. pulchra (XIII, 12)... 138 3 — (XXXIX, 10-13) 384 — elegans (XIV, 18) ee | 45) — nana (XXX, 32-34) 268 — Forbesi (XIV, 1-3) 123, 140 a nebula (XXX, 14-19) ... . 272 — Harrisoni (XIV, 21) 123, 144 = — var. delicatula(XXX,26) 274 — incisa (XIII, 2 es LOS — — var. elongata (X:XX, 20, — Lundgrenii (XIV, 10-14) 123, 148 ad _ i 273 — Nordmanni (XIV, 4,5) ... 123, 146 a — . ginnaniana (XXX, — gyeni (XIV, 19, es ie 123, 148 ey 25) 273 — proxima (XIV, 22 145 — — var. levigata 275 — Ravni (X1V, 15-17) 142 — nevropleura (XX XIX, 6) 383 = — (XLIV, 21) e ... 359 = nuperrima (XX XIX, 5) 386 | Seila trilineata - x mk ... 424 — Payraudeaui (XXX, 38) 262 | Semicassis (s.-g.) saburon 59 — Payraudoti 263 | Serpula glomerata 459 — plicatella (XXX, 7) 258 Se intonta mS 457 _ proxima. ... 383 | Sipho brevispira oe dose = ect ubSe — senilis (XXX, 3). 264 | — cordatus (XXII, 5) 179, 185 — sigmoidea aa eae) — costiferus 137 — similis (X XIX, 28, 29) 259, 261 — ecretaceus 149 Smith-Woodwardi (XXX,6)... 266 | -— cretosus = ran 149 — stria me 243 | — curtus (XXI, 1, 2) 178, 180, 202 — striatula (XXIX, 26) . . 20) — — var. brevicaudata (XXI,4)... 179 — substriolata (XXXIX, cen 15) 385 = — var. exilis (X XI, 8) PS als) _ tenuistriata (X XIX, 31, 32) ... 263 | — — var. incurvata (XXJI, 6) 179 chet ae (OXON: 16) 984) || <== =) “var date (xxae7) 179 INDEX. 479 = exilis|((UES45 5) mee ae ee 54 PAGE PAGE Sipho curtus, var. longicaudata (XXI, 5)... 179 | Sipho tortuosus, var. attenuata (XXIV, 5, 6) — — var. solida (XXI, 3) ... oe eh’) 183, 191 — ebur (XXII, 13, 14) ... eS! « 197 — o var. lirata (XXIV, 11-15) 123,192 — elegans (XXIV, 7, 8)... st x» 199 — — var. turrita (XXIII, 15,16) 191 — exiguus (XXIV, 10) Gee = 199 — ventricosa es ma en ty — glaber (XXIV, l, 2) ... 24) 268)|.*— “Verkriizent) ... #1 x a dag — ae (EK: 3, 4) See ae 175, 177 — _- var. plicifera * ay) AS — (COX KY LEE Se. 372 — (s.-g.) virgata . oh, ob soot pile — — _ var. convoluta (XXV, 6, 7)... 178 | Siphonorbis (s.-g.) ebur rs. Ea yl o7 — — — (XXXVIII, 3, 4) 372 — elegans ... Bon ... 364 = == var. Coulsoni (XX, 5,6) ... 177 a latericeus 40 .. 304 — — var. elongata (XX, 7) oe Ye — propinquus fi 1a, 1800 — — var. glaber ... 188 = togatus ... ae tog SO — Herendeenii (XXII, 11; XXV, 8, 9) 184 — turritus ... ihe ne hall — hibernicus ae % : i Ode aa undulata A 137 — hirsutus (XXV, 10) ... 201 | Smithiella (s.-g.) costulatum striolatum 248, 270 — islandicus (XX, l, 2) 7 ... 187 | Spherium corneum ... ee sis 42, 48 — — (X XXVIII, 5-8) ... ... 873 | Spheronassa mutabilis 5 ee wv ) ol — Jeffreysianus (XXIV, 3, 4) ... ... 196 | Sphyradium edentulum _ a TRyAS == -- (XXXVITI, 12) ... 873 | Spirotropis carinata ... me) a) — Kroyeri F <2 48 — modiola (XXVIII, g- 12) ... 2380 — latericeus (XX, 10, ll, 12). ... 189 | Stenomphalus Wiechmanni (XII, 31) Boe eA) — — CXXXVIT, 14)... ... 874 | Strombiformis reticulatus ... ee ... 414 — Leckenbyi Ae ... 875 | Strombus norvegicus ae Nee leat — menapie (XXIII, 17- 19) a 123, 186 — __ pes-pelicani ok aa: 432 = — var. hibernica (XXIII, 17) 373 | Succineaelegans ...... ee HL, 48 — minimus (XXIII, 4) ... ane ... 189 — oblonga (I, 13)... ae 22, 48 — Mebi ... : 1 97 — putris ae 3 won Pell, PBI, 41} — Olavii (XXIII, 5, 6). 352 176,193 | Surcula consobrina ... abs jae OS — —_ var. conulus (XXII, 14) ... 195 | Sveltia Lajonkairei (XL, 18- 21) i ee ood — — _ var. Morchii (XXIII, 7-9) ... 194 — varicosa (XL, 15-17) ce eos — pertenuis mh. ois ae ee OAs — propinquus (XX, 8, 9) oe ... 195 | Tachea (s.-g.) hortensis se i ay HG — -— (CXEXOXGV NIT, 9) ... 3¢5 | Taranis Alexandrina See ee .. 302 — pupoidea st Sa 86 — cirrata oe ste re wea) o02 — pygmeus (XXXVI, 13-15) Lp eee — emendata ... 2) tebe Pa? — Sabini, Leche ... sae .. 184 — Morchi (XXXII, 34) Ae .. 801 — Sabinii, Gray (XXII, jie B)) ee .. 183 | Telasco (s.-g.), see Nassa_... aa .. 9323 — Sarsii (XXII, 12)... en 197,198 | Tellina amnica ic oe BG wel Ai — + var. crassa (XXIV, 9) .. 198 | — _balthica a aa ... 5, 85, 37, 40 — togatus (XXII, 1, 2) ...180, 184, 202 | — calcarea cf ee ee ae All — — var. brevispira (XXII, 7)... 182) — _ cornea ae a aa Be wae —_ — var. crassa (X XII, 6) sso ts) calito Se oe cP Too, = = var. Frielei (xd) 3,4) .. 182 | — Henslowana ... He oe 46 == — var. minor (XXII, 8-10) ... 183 | Terebra canalis (II, 1) rt L joan 8 = — var. sinuosa ... BS. woe LRA — var. acuminata Vai an 04 — torrus (XXXVIII, 10, 11) Ey oul Met — var. costata (II, 2 Lae OO | — tortuosus (XXIII, 10-13) ...176, 190, 372 4.80 INDEX. PAGE Terebra inversa sd io e ral ios — — var. costata (II, 7) . 54 — — var. dextra ... aa fs oS — — var. dextrorsa a8 ay me Terebratula grandis ... 5, 60, 62, 137 Teretia (s.-g.) emendatum ... she pe eed Tetrastomella (s.-g.) subulata fi ie OO. Thiarinella (s.-g.) compta ... $e zp gob Torellia vestita on ae am “Sk Trichotropis arctica ... By Be .. 429 — atlantica AK va x, /428 — borealis (XLIV, 36-38) ... 428 — — var. incrassata s» 450 — dolium ... nf “ee carat 4i2d. _ insignis (XLIV, 39) ... ... 480 es — var. Woodii (XLIV, 40) 430 — Kroyeri (XLIV, 35) ... .. 429 Triforis adversa By f adi w. 425 — Fnitschii... oh ie ... 426 — Macandrewee ao a we, ADT — perversus ... em: sis ... 426 - — var. adversa (XLI, 25)... 425 Trigonostoma acutangulum (XL, 2) aol — ampullaceum (XL, 1) .. 399 umbilicare (XL, 3, 4) ... 400 Triphora perversa... +e ‘oe ... 425 Tritia (s.-g.) trivittata ae bay ie 21 | Triton connectens ... a4 Ai ee a — heptagonum (XII,6,7) ... ... 120 — — var. pyrenaica .. a 20 — Woodii ea a ee sev ele Tritonella (s.-g.) incrassata ... Ma en oud — pygmea ... ee foe Bate Tritonia varicosa ... ke ie . 326 Tritonium antiquum, var. behringiana ... 164 — craticulatum ae Hee 130, 345 — greenlandicum, var. perdix ae OZ — Gunneri ... i a: tay es — incarnatum ae Pra sow Alte — islandicum 5a oe me LS? — mitrula... a ae Boer) ASKS — perdix ... Soe ane OZ — propinqguum ms ae Soo NS — pusillum ... te De » 135 == pyramidale sen 5o8 OO —- roseum ... ae ae ce 208 — Sabini, Leche... i Ron etter! PAGE Tritonium sitchense ... 137 terrze-nove 100 turricula ... 293 turritum ... 191 viridulum 406 Tritonofusus (s.-g.) costiferus 137 — — ebur 197 = — gracilis... 175 — — Herendeenii 184 _ — Kroyeri 148 — — latericeus 189 Trivia affinis .. 50 avellana 50 europea 49 — var. affinis 50 — var. coccinelloides 49 — var. globosa... 50 — var. major 49 — var. minor ade ec) — var. sphericulata (II, 15, 16) 49,51 pisolina (II, 17) 50 sphericulata ... 49 Trochus perversus 425 Trophon Actoni 152 altus ae 150 — var. costellatus 151 alveolatus &: 146 — var. consocialis ... 147 antiquus 168, 368 — var. carinatum 161 — var. contrarium ... 156 — var. contraria carinata ... 3866 — var.contrariumangulatum 160 — var. despecta 161 — var. jugosum 162 — var. striatum 169 Bailyi 131 berniciensis 363 consocialis 147 costifer 35 costiferum = 86 craticulatus 130, 345 elegans 115, 364 gracile 176,178 imperspicuum 360 Kroéyeri 148 Leckenbyi ... 375 latericeus 374 Trophon Morchii INDEX. PAGE | 302 | norvegicus ... 153 propinquus... 192, 376 — var. contortus .. exo USB} Sabinii, Gray “184, 199, 374 Sabini, Leche ne, .. 184 scalariforme 127, 350, 351 | tortuosus 180 | Turtoni ae elOm ventricosus ... 171, 369 | (Boreotrophon) Bamffius 128, 201, 349 clathratus (XII, 25) 127, 201 (XXXVI, 3-5) 349, 350 —- var. attenuata (XXXVI, 7,8) 351 349 var. Bamffius var. exilis (XXXVI, 9,10) 352 var. Gunneri 128, 352 | = — var. lamellosa 128 = — var. minor (XXXVI, 6) 351 var. scalariformis, S. V. Wood 351 een — var. truncata 129 = clavatus ... cre 258) | = Gunneri (XII, 26) 128 == — (XXXVIII, | 19,20) 352 = — var. Coddii (XXX VIII, 21) 353 — mediglacialis | (XXXVIII, 22) 353 — truncatus (XIT, 23, 24) 129, 203 — (XXXVI, 22, 23) 349 — var. Harmeri (XXV, 13) 201 — var. intermedia (XXXVI, 24) 350 | — var. major | (XXXVI, 25) 350 | 128 — — var. scalaris ... (Trophonopsis) barvicensis (XL, 29, 30) 357 Bailyi (XII, 29) ... Trophon (Trophonopsis) 481 PAGE Bailyi (XXXVI,11) 355 decoratus ... soo Ox80/ Fabricii (XII, 28) (see also 'T. Kitchini) 130, 358 — var. Bailyi 131,355 Harmeri (XL, 27, 28) 201, 356 Kitchini (XII, 27) 358 Lamplughi(XII,22) 134 muricatus (XII, 18) 131, 133 (XXXVI, 12) 354 var. barvicensis 357 var. Bellii (XXXVI,15) 354 var. cancellata (XXXVI, 16) 355 var. Nysti (XII, 19) 183 var. similis (XII, 20) 133 — -- — — (XXXVI, 13, 14) 354 — — — — (XLIV, 20) 354 — — — var. valida (XII, 21) 182 Trophonopsis muricatus 304 — truncata F Bae .. 9349 Troschelia berniciensis (XX XVII, 15,16)... 363 Turbo acutangulus 44.4, — (s.-g.) biplicata 455 — cylindraceus ... 20 — imbricatarius, Broce.... 454. — marginalis .. 402 — muscorum 18, 20 — spiratus 44.6 — subangulatus ... 443 — terebra 441 — tornatus 455 — tricarimatus 438 — triplicatus 448 — vermicularis 4.49 Turrisipho (s.-g.) tortuosus... 190 Turritella acutangula, Linn. 445 — bicineta 439 — clathratula 442 Paleontographical Society, 1917. A MONOGRAPH OF THE BRITISH PALAHOZOIC ASTEROZOA BY Woe Soh PN CER: Mev D.Se.(Oxon.),, F-G.S. eR LY. Paaes 169—196. LONDON: PRINTED FOR THE PALMHONTOGRAPHICAL SOCIETY. APpRit, 1919: 170 BRITISH PALAOZOIC ASTEROZOA. characters of the adambulacralia. These ossicles are extremely broad, with an oral surface scarcely above the level of the cross-ridge of the ambulacralia, and with a characteristic ornament (Text-figs. 118, 119, p. 174). The alignment of the ambulacralia with the adambulacralia makes the groove very shallow, and the oral surface of the arm flat. This, with the petaloid shape of the arm, produces a leaf-like appearance suggesting the generic name Platanaster for the Ordovician form (aAaravoc, a plane tree, so called from its broad, flat leaf). Although both Platanaster ordovicus and Palasteriscus devonicus have the same peculiar adambulacralia, which, with other characters, show that they belong to one and the same small branch of the Asterozoa, they differ in other ways so con- siderably that one is loth to follow one’s first inclination and put them in the same genus, regarding one species as the ancestor of the other. The earlier form has well-defined infero-marginalia which are lacking in the later species. This in itself would not be an insuperable objection to placing the forms on the same exact line of descent, for it is possible that infero-marginalia may be lost during lineage evolution. A far greater difficulty is the position of the madreporite. In the Ordovician species this plate is apical and marginal, while in the Devonian species it is oral and quite near the mouth. Following the line of argument developed later (pp. 178-182), one would place the first form, with its fused arm-bases (Text- fig. 114, p. 172) and its apical madreporite, with the Asteroidea. It is difficult to explain the position of the madreporite in the later form except by the supposition that its arms never fused at their bases, and so allowed a secondary growth of the apical interradii to carry the madreporite on to the oral surface. This would place Palasteriscus devonicus among the Ophiuroidea, and we should have the paradox of two nearly related forms belonging apparently to distinct branches of the Asterozoa. Fortunately, we have other series of related forms which show similar phenomena. The arms of Stenaster often approximate at their bases because their adambulacralia are so very broad. This character causes fusion of the arm- bases of Monaster, which, according to Schuchert, is allied to Stenaster. The madreporite remains in consequence apical and marginal in this latter form. On the other hand, Aspidosoma, a near ally of Stenaster, has unfused arm-bases, and a downgrowth of the apical interradii, which carries the madreporite to an oral position. We can only suppose that among the earliest Asterozoa the impulse to become definitely either Asteroidea or Ophiuroidea was not fixed. I have suggested below (p. 195) that the “ Asteroid” character of fusion of the arm-bases and the “Ophiuroid” character of downward growth of the apical interradii are both brought about by feeding habits. According to my interpretation, Platanaster ordovicus is a form which has specialised in ciliary feeding, and has developed a large ciliary area by increasing the surface of the infero-marginalia, which in con- sequence meet along the interradii, while Palasteriscus devonicus is descended from PLATANASTER ORDOVICUS. tal a nearly related form with infero-marginalia small or absent, which has taken to mud-eating ; its stomach has become enlarged, and the apical interradii have had to grow outwards to accommodate it. There can be no doubt that the Platanasteride branched off from the Asterozoan stem at a very early date, and had reached a high stage of development in the Ordovician. That the family is far advanced in its lineage history is shown by: (1) The large size of the species. The type is the largest English species of its time, and only the American Ordovician species of Promopalxaster approach it in size. (2) The petaloid nature of the arms. Ruedemann (97, p. 35) has shown that this is a gerontic character in Devonaster. (8) The enlarged mouth-angle plates comparable with those of Promopaleaster (compare Text-fig. 55, p. 96). On the other hand the proximal ambulacralia are in a primitive condition. Usually among the Asterozoa the first ambulacralia are thickened and help to form a continuous ring-shaped mouth-frame. Here they are not thickened, and diverge very considerably from the radial line, forming a deep V in each radius. Similar divergent proximal ambulacralia are found in many other primitive Asterozoa, and Bather (89, p. 165, fig. 3) has figured divergent ambulacralia as a character of Kdrioaster. The diagnostic characters of the two genera are as follows: Platanaster.—Arms fused at the base. Stout infero-marginalia present. Madreporite apical. Palasteriscus.—No infero-marginalia. Madreporite oral. Genus PLATANASTER, novum. Generic Characters.—As above. 1. Platanaster ordovicus, n. sp. Plate XIV, figs. 1—3; Text-figs. 114-118, 120, 121. Material.—One well-preserved impression with counterpart in the collection of the Museum of Practical Geology, Jermyn Street, no. 8238 (mould of apical surface) and no. 25347 (mould of oral surface). General Appearance (Text-fig. 114).—Text-fig. 114 is a reconstruction of one arm and the neighbouring interradiu. The form is so well preserved that the figure is almost an exact drawing from a cast of the specimen. The broad petaloid shape of the arm is brought about by three factors—the great breadth of the adambulacralia, the spimdle shape of the deep ambulacral channel, the decrease in size of both the ambulacralia and adambulacralia from about the middle length 172 BRITISH PALAOZOIC ASTEROZOA. of the arm in both a proximal and distal direction. The first two infero-marginalia are incorporated in the disc. In front of these is a prominent breast-plate-shaped odontophor. The mouth-angle plates are very large and extend backwards as far as the third adambulacral. ‘The cross-section of the arm, given as Text-fig. 115, = ee: Vy oe | ii) oe oree be t ii) Trexr-ric. 114,—Slightly reconstructed drawing of the oral view of an arm and a portion of the dise of Platanaster ordovicus. Ad., adambulacral; Am., ambulacral; J.1/., infero-marginal; J. P., mouth-angle plate; O., odontophor. x 3. shows the shallowness of the groove, the great depth of the ambulacral channel, and the apical covering of uniformly sized paxille. Oral Surface (Vext-figs. 116—119).—The mouth-angle plates are high, narrow wedges which project well beyond the proximal limits of the groove into the mouth-cavity. The proximal extremity of each plate rises steeply and carries a row of spine-pits along its adoral edge. Stout spines, which once fitted on these, still remain scattered between the plates. The slightly swollen inner surface is excavated for the attachment of the first three adambulacralia. The third PLATANASTER ORDOVICUS. 173 adambulacral has fallen away in the mouth-angle drawn (Text-fig. 116), but can be seen in Text-fig. 117, which is an aboral view of another mouth-angle. The clearest: views of the distal extremities of the mouth-angle plates are given in Text- fig. 114. Here they are deeply hollowed, and the odontophor fits across the wide triangular space thus formed. ‘lhe upward tilt of the adoral surface of the mouth- Text-ria, 115.— Cross-section through the arm of Platanaster ordovicus. Ad., adambulacral; Am., ambulacral ; I.M., infero-marginal; Su. Am., super-ambulacral. x 5. angle plates, as shown in the figures, suggests that the form was preserved while the external interdental muscles were in a state of contraction (‘Text-fig. 134, D. MUSC.9, p. 193). The ambulacral groove is wide and petaloid. The broad, short adambulacralia are very slightly higher than the ridges of the ambulacralia. A view of the ossicles %. Me Text-ria. 116.—Adoral view of an angle of the mouth-frame of Platanaster ordovicus. Ad. and Ad.9, the first two adambulacralia; M.P., mouth-angle plate. x 10. of the groove showing full details is given (Text-fig. 118). The ambulacral channel is deep and has precipitous sides. The concavities for the transverse muscles are well marked, suggesting that they were strong. There is a marked overlap of the ambulacralia, which takes the form of a wide curved peg much as in Stenaster (compare with PI. I, fig. 6). The ridges across the ambulacralia are as described for Schuchertia (p. 183). Shght pustular elevations are seen on some of the outer extremities of the ridges of the ambulacralia. Bather has noted (91, IV, p. 123) 174 BRITISH PALAOZOIC ASTEROZOA. that the ridge on the flooring plates of Hdrioaster bigsbyi may be broken up into a row of tubercles. These are the only two instances of this character I have met with among the Echinodermata. There are no pores for the passage of ampulle. The noses of the adambulacralia fit on large triangular faces at the outer edges ivy 118 Text-Fic. 117.—Enlarged view of a mouth-angle of Platanastir ordovicus. Ad.,, Ad.y, Ad.., first, second and third adambulacrals; 1/.P., mouth-angle plate; O., odontophor. x 8. Text-ria. 118.—Enlarged view of a portion of the groove and neighbouring ossicles of Platanaster ordovicus. Ad.,adambulacral; 4m.,ambulacral; /.M.,infero-marginal. x 10. of the ambulacralia. Between the noses are shallow depressions for the tube-feet. Kach nose is continued as a sharp ridge across the adambulacral for about two-thirds of the breadth of the ossicle, after which the ridge broadens and dies gradually away, forming an outer triangular area which carries oblique transverse rows of Text-riG. 119.—Enlarged view of a portion of the groove and neighbouring ossicles of Palasteriscus devonicus. Ad.,adambulacral; d4m.,ambulacral. x 4. spines. Single spines are carried by the ridge right up to the point where the nose fits on to the ambulacral. The occurrence of these inner spines is interesting, because it shows that the linear arrangement of the ambulacralia and adambula- cralia is a natural one, and not due to the collapse outwards of the adambulacralia after death. If during life the adambulacralia had stood, as is usual, at more or less a right angle to the ambulacralia, the walls of the groove would have been Or PLATANASTER ORDOVICUS. i? very steep and the spines unnecessary. A widely open groove would necessitate, on the contrary, the protection of the tube-feet by spines carried in the fashion described. The adambulacralia are closely touching and slightly ridged at their points of contact. It is difficult to imagine that the arms had much power of flexion. At one point the ambulacralia and adambulacralia have been pushed away by post- mortem disturbance, and the base of a super-ambulacral plate is seen. The infero-marginalia throughout the greater part of the length of the arms are closely-fitting plates alternating with the adambulacralia. They possess a large outer flat area ornamented with pustules, and a small inner sunk unornamented area. At the extreme tip of the arm they become globular. The two infero-marginalia which meet at the base of the arm are the largest and are sickle-shaped (Text-fig. 114). Just within the dise are two large plates Text-Fia. 120,—Drawing of a portion of the apical surface of Platanaster ordovicus. Am., ambulacral; I,.M., infero-marginal; Px., paxilla, x 12. which suggest, both by general appearance and ornament, that they are infero- marginalia incorporated into the disc by fusion of the arms at the base. The main axis of these plates is also sickle-shaped. Apical Surface (Pl. XIV, fig. 1; Text-figs. 120, 121).—A side view of the original impression of the form shows that the broad bordering plates are the infero-marginalia. The apical surfaces of these are very similar to the oral faces described already. The remaining portion of the apical surface was originally covered with long slender paxillze in rows alternating with the infero-marginalia. The paxille have fallen away from the central portions of the disc and exposed the mouth-frame. The proximal ambulacralia distinctly diverge, forming descend- ing V’s along the radu (Pl. XIV, fig. 1) and ascending A’s along the interradii. Text-fig. 121 shows one of these ascending A’s. The tip is occupied by the highest portions of the mouth-angle plates; the greater part of these plates lies too low to be in view. The groove pointed to by the dotted line reaching to the letter A is the groove for the water-vascular ring-canal. The canal was plainly carried along the top of the ambulacralia constituting the V. The course of this 176 BRITISH PALAZOZOIC ASTEROZOA. channel was not recognised, however, until the figure had been drawn, and it is not shown. The A is kept in position by the odontophor, which has wide flanges fitting against outer flanges of the ambulacralia. The intimate connection and close fitting of these components suggest that the odontophor played a very important part in holding the mouth-frame together. Here and there accessory stiffening plates (Text-fig. 115) are exposed. I have termed these “‘superambulacralia,” after the plates of similar function in the recent Astropecten. 'The madreporite is a long, roughly elliptical plate, situate near the margin (Plate XIV, fig. 1). The madreporiform markings are faint. Trext-ria. 121.—Wash drawing of the apical view of the interradial mouth-region of Platanaster ordovicus. A., ascending limit of the mouth-angle plate ; d4m., ambulacral; O., odontophor. x 10. Measurements.—R :r::43 mm.: 15mm. Width of arm at the base is 17 mm. Horizon and Locality—Upper Ordovician (Caradocian) of Cound, Madeley, Shropshire. Genus PALASTERISCUS, Stiirtz. 1886. Palasteriscus, Stirtz, Paleontographica, vol. xxxii, p. 95. 1890. Pe Stiirtz, Paleontographica, vol. xxxvi, pp. 228-225. 1893. - Stiirtz, Verhandl. Naturh. Ver. preuss. Rheinl., Jahrg. 50, pp. 44, 61. 1900. 3 Gregory, Lankester’s Treat. Zool., vol. iii, Echinoderma, p. 257. 1914. Ls Schuchert, Fossilium Catalogus, Animalia, pt. 3, pp. 5, 8, 32. 1915. * Schuchert, Bull. 88, U.S. Nat. Mus., pp. 44, 199, 200, 252. Generic Characters.—No infero-marginalia. Madreporite oral. Stiirtz, as was his custom, tried to establish relationships of his genus with recent Asteroidea. At first (1886) he thought that these were with Asterina and Palmipes (= Asteriscus, Miller and Troschel), but later (1890) he decided that its PALASTERISCUS. IAG real kinship was with Solaster and Valvaster, and as these were put in the recent family, the Kchinasteridz, he founded for it a new family, the Palechinasteride. Gregory (1900) founded the family Palasteriscide for Palasteriscus and Hehin- asterella. Schuchert (1914) enlarged Gregory’s family by the addition of Cheiropteraster and Loriolaster. The structure of these latter three genera will be dealt with later. They have a very different structure from that of Palasteriscus. The only species is Pulasteriscus devonicus, Stirtz, from the Lower Devonian slates of Bundenbach, Germany.! ‘Three specimens, including Stiirtz’s type, are preserved in the British Museum (Nat. Hist.) nos. E. 3466 (the type), H. 3407, and HK. 5026.