» THE DANISH INGOLF- EXPEDITION. VOL. II, PART 5. CONTENTS: AD. S. JENSEN: L AMELLIBR ANCHI ATA, PART I. ^^ ^ PUBLISHED AT THE COST OF THE GOVERNMENT — tr '-^ BY j^^p r^ ' THE DIRECTION OF THE- ZOOLOGICAL MUSEUM OF THE UNIVERSITY. :^^= □ t ""-^i^JjMii^" COPENHAGEN. H. HAGERUP. PRINTED BY BIANCO LUNO. 191 2 THE DANISH INGOLF-EXPEDITION. VOLUME II. 5. LAMELLIBRANCHIATA (PART I.) BY AD. S. JENSEN. WITH 4 PLATES AND 5 FIGURES IN THE TEXT. ■^"^::>^-<- COPENHAGEN. PRINTED BY BIANCO LUNO. 1912. l~-r- Read}' from the Press October 23''' 1912. CONTENTS. Lamellibranchiata, Part I. Page Introduction i Anomia 3 — patelliformis L 4 — sqnajmtla L 5 [Osirea edulis L.] 11 Pt'ctcu pitsi'o L II — opercularis L 13 — islandictis M ull 15 — aratus Gmel 19 — scptemradiattis M ii 1 1 20 — tigrmiis W ii 1 1 22 — striatus Mull 24 — imhrifer Lo v 25 — vitreiis C h e 111 n 27 — simtlis Lask 29 — groenlandicits Sow 30 — frigidtcs Jensen 33 — 2indatus Verr. & Smith 37 — maxintiis L 37 Atmtsshim luciduni J ef f r 37 Lima loscotnbii Sow 3^ — excavata F a b r 39 — gwyni Sykes 4° — hyperborea Jensen 41 — subauriculata Mont 42 — similis n. s p. 44 — subovata Jeffr 44 — ingolfiana n. s p 45 — j^ff'"'^}'^' Fisch 45 Page Lima sarsii L o v 46 Mytilus fdnlis L 47 Modiola modiolus L 48 — phaseolina Phil 51 Dacrydium -ritreicm Moll 53 Idas argtntftis Jeffr 5^ Modiolaria 57 — discors L 57 — corrugata S t p s 62 — nigra Gray 63 — f aba V ah r 66 CreneUa decussata Mont 68 Cardium echinatiim L, 71 — [edule L.] 73 — minimum P h 74 — fasciatum Mont 75 — \nodosum Turt] 79 — ciliatum Fabr. 79 — elegantulujti Moll 84 — \norvegicutn S p g 1.] 85 — groenlandicum Ch 85 \Isocardia cor L.] 89 Cyprina islandica I, 89 Astarte borealis C h. 92 — Montagui D i 1 1 w 97 — sulcata D. C 105 — elliptica Brown 108 — crenata Gray 113 41873 Introduction. The Danish Ingolf-Expedition of 1895 — 96 brought home a ver>' considerable material of Mollusca from the waters round the Faeroes, Iceland and South Greenland. The Expedition was planned on the lines of a deep-sea investigation and the greater part of the material collected comes therefore from great depths; of the 144 stations investigated no less than 125 have depths of over 100 fathoms. This material is naturally of great interest; the area investigated was but little known before and an extension of our knowledge of the deep-sea fauna must be classed among the relatively rare occurrences. Whilst working tip this material I felt appreciably the lack of information regarding the distribution of tlie Mollusca in the coastal regions round a great part of the area. This does not apply however to Greenland; on the west coast of that country collections have been made for many years and the material has been worked up by H. J. Posselt, and from the east coast the gatherings of the expeditions of recent years have been worked up by Posselt, R. Hagg, Ad. S. Jensen and J. Grieg. From Iceland and the Faeroes, on the other hand, we had, just as previously for Greenland, but incomplete and short lists of the species and, as these, mainly drawn up by O. A. L. Morch. This deplorable absence of material from the coastal region of Iceland and the Fjeroes has now been made good. In 1892 and 1893 already Mag. scient. Will. Lund beck had collected a great number of JMolIusca in the north-western fjords of Iceland during his voyage with the fishing-cutter "Prinsesse Marie" and in recent years a number of the jounger naturalists, who have visited the P'aeroes and Iceland, have willingly met my wishes and made a special effort to collect the Molluscs of those regions. I may thus mention in particular, that in the summers of 1898, 1899 and igoi Mag. sc. R. H or ring made considerable collections at the Faeroes and along the east and south-west coasts of Iceland during his cruises with the fishery-inspection ship the "Diana"; further, that Dr. A. C.J oh an- sen in 1900 brought home a large collection from the east and south coasts of Iceland, also made during a summer cruise with the cruiser "Diana". In 1902 Mag. scient. A. Ditlevsen was sent out with the "Diana", in 1903 Mag. scient. C. V. Otterstrom with the new inspection-ship "Beskytteren", in 1904 Cand. magist. H. J. Gemzoe ("Reskytteren"), in 1905 Cand. F. Johanseu ("Beskytteren") and in 1907 Cand. magist. O. Bornp ("Be.skytteren") ; all of these l>roug!it home collections, which helped to throw light on the Mollnscan fauna of the Faeroes and Iceland. The Inoolf-Expedilion. II. i- I LAMELLIBRANCHIATA. Information with regard to the Molhiscan fauna of our North Atlantic islands was also obtained from another side. The Icelandic botanist, Dr. Helgi Jonsson, who was dredging for algae at the Faeroes and Iceland during the years 1897, 1898 and 1901, in response to ra}- request, preserved the Molluscs collected at the same time and with great liberality presented them to the Zoological Museum of Copenhagen University. His countryman, the zoologist Bjarni Scemundsson, has also assisted me, among other ways, by lending material from the Natural Histor\- Collection at Reykjavik. A very considerable collection has been brought home from the Faeroes by Dr. Th. Morten sen, who in 1899 carried out a series of dredgiugs from the gunboat "Guldborgsund" partly in the fjords, partly on the banks down to a depth of ca. 150 fm. Lastly, Dr. Joh.s. Schmidt, the leader of the cruises with the research-steamer "Thor", has during several years made collections at the Faeroes and Iceland and brought home a considerable and very valuable material, from the littoral right down to the abyssal region, which he has preserved for science by presenting it to the Zoological Museum of Copenhagen. For the sake of completeness I may further mention, that during my participation in the 1902 cruise of the research-steamer "Michael Sars" under the direction of Dr. J oh an Hjort, I was given the opportunity of collecting a quantity of Mollusca on the banks round about the Faeroes, on the east coast of Iceland as well as north and south of the Wyville Thomson Ridge. During ni}- voyages in West-Greenland in 1906, 1908 and 1909 I also collected a great number of Molluscs. The present part of the work on the entire material will show, that my endeavours have been directed first and foremost to the disentanglement of the species. The determinations have been made as carefully as possible; that we can not be sufficiently critical regarding the determinations made by our predecessors, even of common and apparently well-known species, I have alread\- shown in my small papers on Mya and TclUiia. With respect to Greenland, I have restricted myself to give a brief review of the distribution, as the works of Posselt and others have already discussed the details. For Iceland and the Faeroes, on the other hand, each single place of occurrence has been mentioned, as there is a need here for all the information we can obtain — better to have too much detail than the reverse. With regard to the synonym)' lists I may remark here, that they have been intentionally divided into two sections, the first referring to the most necessary, systematic literature, wliilst the second contains references to the principal, local fauna-lists. The region dealt with here — the "bridge" between Europe and America across the North Atlantic Ocean and the slopes down to two deep-sea basins very different in hydrographical regards — offers more than ordinary interest, and many and varied problems have presented themselves for discussion as the work advanced. But the treatment of these and other conditions I shall postpone meantime, until the systematic elaboration of the material is completed. Copenhagen, Zoological Miiscnni, October igii. Ad. S. Jensen. Lamellibranchiata. Part I. Anomiidae. Anomia. The genus Anomia is represented by 2 species at the Fteroes and Iceland: Anomia sqnaiiinla L. and Anomia patclliformis L. As regard the former, I am unable to agree with the prevailing view that A. sqiiamnla. is a variety of A. cphippiuni. The latter is considerably larger and easily distinguished from the fact, that the upper (free) valve of the shell has 3 muscular impressions (one of the adductor, two of the byssus musculature; comp. PL I, fig. 3), whilst the upper valve in A. sqnamula only shows two muscular impressions (one of the adductor, one of the byssus muscle). Anomia aculeata IMiiller (PI. I, fig. 2 d) I take to be a variety of A. sqiiamnla, as there are all transitions between smooth and spinous specimens and they agree exactly in other regards, e. g. in the byssus musculature. G. O. Sars has observed correctly in so far that he only found two muscular impressions in the upper valve of A. aailcata and was consequently disinclined to refer A. aculeata as a variety to A.ephippiiim^ where there are three muscular imprints') on the upper valve. But Sars has not noticed at the same time, that ^i. sqnamula also has only two muscular impressions (PL I, fig. 2 c) and consequently cannot be a variety of ^i. cphippiuni either. I have sought in vain for the true A. tphippium in my material from the Fseroes and Iceland. Nor have I found this species among the material which has been collected in the course of years in the Danish waters. It is perhaps even doubtful, if A.cphippium occurs at Norway; I do not think it altogether inconceivable that G. O. Sars, starting from the anticipated view that A. squamula is a variety of A.rp/iippitim, has ascribed to A.cpiiippium a distribution in Norway on this erroneous basis 2). Again, it is difficult enough to distinguish Anomia pafcliiformis from A. squamula — and prob- ably not always with certaint\-; the upper valve shows only two muscular impressions in both species (comp. PL I, fig. I c with fig. 2 c). The best distinguishing marks are, that the notch in the lower valve is large, almost triangular in A. pafcliiformis (PL I, fig. ib) and the umbo a little way from the margin (PL I, fig. I a), whereas in A. squaviula the notch in the lower valve is small, oval (PL I, fig. 2 b) and the umbo entirely or almost on the margin (PL I, fig. 2 a). 1) It is not quite fortunate, when Sars describes the adductor imprint as being bi- or tripartite. 2) Linne also has his two species geographically separated, the main region for A. ephippium being given as the Mediterranean, whilst A. squamula hves "in Oceano Svecico". Sjst Nat. ed. 12, 1, 2, 1767, p. 1150 and 1151. I* LAMELLIBRANCHIATA. Anomia patelliformis Liime. PI. I, figs. I a — c. Anomia patiUi/orm is Limie, Syst. Nat. ed. 12, I, 2, 1767, p. 1151; Jeffreys, Brit. Condi. II, 1863, p. 34, pi. 20, fig. 2; vSars, Moll. Reg. Arct. Norv., 1878, p. 15. ^iiioinia patcllifonnis Morch, Vidensk. Medd. Naturhi.st. Foren. 1867, p. 99. Iceland. At this island, from which it has not been known earlier, the species has been taken in recent years mostly on the south coast, rarely on the southernmost part of the west coast, from the beach down to a depth of ca. 70 fm. West Iceland: 64°45.8' N. L., 23°55.2' W. L., 30 fm i valve. 64°ii'-64°i8.5'N. L., 22°3o.5'— 22°46' W. L., 14-29 fm i — Reykjavik i spec. South Iceland: Grindavik 2 valves. Vestmannaeyjar, shore 2 spec. — 10 — 20 fm 2 — — ca. 20 fm I — — 30 fm., gravel with shells 12 valves. — Heimaey, shore 13 — 63°3o' N.L., 2o°i4' W.L., 42 fm 6 - 63°2i' — , i7°3i' — , 69 fm., black .sand i spec. 63°2i' — , I7°i5' — , 58 fm I valve. 63°3o' — , 17° — , 57 fm I spec, (from stomach of a cod). The largest specimen has a length of 47 mm The Faeroes. When Alorch published his list of the moUuscan fauna of the Fseroes, only one specimen was known, locality not stated; during the latest years it has been taken at the following places: 62°29' N. L., 7°37' W. L., 60 fm., sand and shells i spec. Ejde, 5—6 fm., coarse black sand i valve. Skaalefjord, 4 — 10 fm 2 — Solmunde, on Scrpiila tubes 5 — Kongshavn, 12 — 16 fm 9 — Vestmanhavn, 10—30 fm i — 5 miles N. of east point of Myggenas.s, 50 fm i spec. & i \'alve. 7 miles N. by E. of east point of Myggentes, 57 fm 2 valves. 6i°4o'N. L., 7°4o'W. L., 135 fm i valve. Akralejte in N. 57 W. 12 miles, ca. 150 fm i — Fseroe Bank, 58 fm 2 \alves. 6i°N.L., 8°52'W.L., 90 fm i spec. LAMELLIBRANCHIATA. The larji'C.st specinieii measures 35""". Among a niiniber of s])cciiiicns collected at an earlier date, the locality not stated more precise than "the Faeroes", the largest measures 40""". The greatest depth at which an adult specimen has Ijeen taken is 60 fm.'). Distribution. Apart irom .South-West and South Iceland and the Faeroes, Ainniiid piililli/oniiis occurs along the Norwegian coast from Lofoten southwards (0-40 fm.), and rarely iu the northern and eastern Kattegat (10 — 25 fm.). It is found on all the British coasts (10— 86fm.), north and west coast of France, at Spain and Portugal, iu the Mediterranean and Adriatic. Anomia squamula Linnc. PI. I, figs. 2 a — d. Anomia squaiiiiild Liune, S\'st. Nat. ed. 12, I, 2, 1767, p. 1151. — Aiioii/ia rpliippinin P'orhes & Hanley, Brit. Moll. II, 1S53, p. 325 (partim); Jeffreys, Brit. Couch. II, 1S63, p. 30 (partim); Sars, Moll. Reg. Arct. Norv., 1878, p. 14 (partim?). — ^inoiina acideata Miiller, Zool. Dan. Prodrom., 1776, p. 249; Sars, Moll. Reg. Arct. Norv., 1878, p. 15, PI. 19, fig. i. Anomia squamula Morch, Vidensk. Medd. Naturhistorisk P'oren. 1867, p. 98; ibid. 1868, p. 226. — Anomia cphi/>pium Morch, ibid. 1867, p. 99. The Ingolf-Expeditiou has taken this species at: Bottoin-teiiip. St. 51. E. of Iceland 68 fm. 7°32 C. 5 spec, (on Bugula). - 127. N. - — 44 - 5°6 - 8 — (on Horncra and Biignhi). - 129. N. W. of Iceland 117 - 6°5 - i — - 16. W. - — 250 - 6°i - 7 — (on S€rpula^Ttibulariaa.nACidariss^\\\eii). - 86. — - — (Brede Bugt) 76 - Several hundred valves and i spec, on a Hydroid. - 87. — - — — no - Several hundred valves and 3 spec, on Arc furus Baffini and 7 spec, on Tubularia. - 98. — - — 138 - 5*^9 - Several hundred valves and i spec. - 89. — - — 310 - 8°4 - 2 spec, (on Brachiopod and Cidaris spine). - II. — - — 1300 - i''6 - 3 valves (apparently old). 9. — - — 295 - 5°8 - I sj^ec. and i valve. - 8. S.W. - - 136 - 6°o - I — - 85. — - — 170 - 3 valves. - 67. S. - — 975 - 3°o - I .spec, with 3 others on it. - 54. S. E. - — 691 - 3°9 - I - - 55. — - — 316 - 5°9 - 4 — (on Oculina and on Cidaris .spine). 6. — - — 90 - 7°o - 6 — and 7 valves. 1. W. of the Fseroes 132 - 7°2 - 5 — (on Cidaris spines and on shell of Pcctcn scptcinradiatjis). The greatest dejJth at which any living specimen was taken was 975 fm., but they may have been attached to two large pieces of timber brought up iu the trawl; otherwise the greatest depth was 691 fm.; the other depths lie between 44 and 316 fm. ■) The specimen from 90 fm. is very small, 5™"'. long. LAMELLIBRANCHIATA. The specimens from deep water are more or less thin-shelled and of small dimensions; of those from 170 fm. and more the largest specimen is 11.5"'"' long. Some of the many shells from St. 86, 87 and 98 belong to the variety acjilcata. Besides, the tendency of the species to vary is shown in a remarkable power of changing sculpture and form according to the substratum, possessed not only by the valve which is closely adherent to the substratum but also by the free, upper valve. Thus a specimen on Rctepora has a pitted surface on the uj^per valve, where the pits correspond to the openings in the network of the Bryozoa; a second specimen shows spinous ribs corresponding to the costce of the Pcctoi scptcin- radiatus to which it is attached; a third on a spine of a Cidaris shows folds or wrinkles corresponding to the longitudinal ribs of the spine; a fourth specimeu attached crossways on a Scrpitla tube has sharp ridges opposite the rings of the tube, and so on. The contour of the shell is as a rule circular, but sometimes the length is considerably greater than the breadth or the reverse or the contour becomes very irregular according as the substratum restricts the growth in the one or other direction. Iceland. In addition to the specimens from the "Ingolf" stations, Auoiiiia sqiia inula has been taken at Iceland in recent years at other places, east, north, west and south, as is shown by the following list. Eastlceland: Myre Bugt 26 fm. 7 spec, and 10 valves. — ■- 36 - I — L,6nsvik 40 - , mud and clay. i valve. 64°27'N. L., i3°27'W. L 84 - Many spec, on Balaiins Haincri. The Horn N. 74 E. 9 miles .... 38 - 2 spec. 64°58' N. L., i3°25' W. L 40 - 3 valves. Faskrudsfjordr 50—20 - , blue clay. i — Reydarfjordr 14 - 2 .spec. Vidfjordr 8—12 - 6 valves. Nordfjordr 40 - i — Seydisfjordr at Skulavig 6 - i spec, and 18 valves. — - - 30 - 3 - Bakkafjordr 12—15 - , black sand. i valve. — 20—28 - , sand and clay. i spec. — 32—25 - , sand and clay vith shells. 3 valves. The largest specimen measures 15.5""". North Iceland: 66°32' N. L., I5°i5' W. L 75 f™- i .spec, and 2 valve.s. Thistil Fjordr 10 - 2 — on algse, 3 spec, on Cy- priiia and 9 spec. — — 50-1 clay vith stones. i valve. LAMELLIBRANCHIATA. 7 Thorshofn 6 fm. 35 valves. Vidarvik ii- 2 — — 13'/^ - , black sand. 6 spec, and 4 valves. Haganesvik S'A— 4 - 5 valves. Axafjordr 22 - , mud. 3 spec. |[ on Pcctrii islaiidiciis) and 7 vaK'es. — 30 - , sand and stones. 18 valves. Grjotnes 12 — 15 - 2 — Skjalfaudi Bngt V- - ^ ^'"^1 '^lack sand. i spec, and 2 valves. Ofjord S. of Hiisey 18 - , cla\-. i — — - - — 17 — 20 - , stones and mud. 2 valves. Hedinsfjordr 13 - i — 66"i7'N. L., i8°i3'\V. L 52 - 8 spec. Kollafjordr 5- i — Skagastrand 15 — Prestbakki 3—4 - 2 — 66°i7'N. L., 2i°i4'W. L 95 - i — (on Bugiila). 66°36' - , 2i°57' - .... 32-37 - II - The largest specimen measures 20.5"'"'. A few belong to the variety aculcafa. West Iceland: Hofuvik 9— lofm. 2 spec, and 3 valves. Adalvik 6— 9 - 3 — Isafjardardjnp 60—63 - 23 — Skutulsfjordr . 2 — 4 - i — Arnarnes 5 — 7 - i — Gnundarfjordr 11- i — 66°8'N.L., 24°2i'W.L 47 - 2 — and 3 valve.s. Dyrafjordr, inside Thingnses io'/2-i2V2 - , ooze and small stones. 15 valves. — 191/, - 2 spec. 65=52' N.L., 23°58'W.L 33 - i valve. Aruarfjordr 10 - 2 spec. 64°45.8' N. L., 23=55.2' W.L 30 - 10 — (2 on Hyas). Talknafjordr 15 - 2 — Stykkisholmr 6—9 - 14 — Hvalfjordr 24 - i — and 25 valves. Krossvik 8 - , shell-gravel, blue clay, stones. 12 valves. Faxafjordr i4'/2 - 2 spec, and 2 valve.s. — 17-1 coarse shell-sand. ca. 100 valves. — 14-29 - - 13 — LAMELLIBRANCHIATA. Faxafjordr, ca. 3 miles N. 59 W. from Grotta lighthouse . . 25 fm. 8 valves. — , off Kollafjordr . . 8 — ii'/a - , mud and stones. 5 spec, and 2 valves. — , mouth of Kolla- fjordr 9Y2 — II - , fine, black sand and mud. 12 valves. — , off Kollafjordr .... 10 - 17 — — , Keflavik 15 — 16 - , fine, black sand. 8 — — , ca. 2 miles N. E. of Kefla- vik 1972 — 20Y2 - 10 — — , I mile W. of Helgasker Vager 13 — 16 - 4 — — , I mile W. of Helgasker Vager 1472 - i — (on Pcctcii islaiidiciis). — , E. of Videy .... 9 — 10 - , fine sand and mud. 5 — — , 7 miles N. N. E. of Ska- gens light . . . 17—2072 - , sand and sheiks. i — Reykjavik, on Laiiiinaria driven on land. ca. 80 spec. — , at low-water mark i spec. — i'/2 fm., stony bottom. 9 — — I'A - . gravel — i — — 3 — 3 - , on Laininaria hypcrborca. 15 — — 8 - 2 — — (Engey) 7 — 8'/2 - , mud. i spec, and 3 valves. Hafnarfjordr, on the beach 10 — — 4 fm., sand and mud. i valve. — 25 - , fine, black sand and mud. 10 — Skagi 21 - 13 — The largest specimen is 22 '""' long. A number of specimens belong to the variety aciilcaia. South Iceland: 63°i5'N.L., 22°23'W.L. . . . 170— 114 fm. 63°i8' - , 2i>' - 94 - 63°3o' - , 2o°i4' — 42 - 63°o5' - , 20° 7' — 293 - Vestmannaeyjar, beach — 10 fm. — 15-20 - — 30 - , shell-gravel. — 49 - , clay with a little mud. — Heimaey, beach 62°57'N.L., i9°58'W.L 500 fm. 2 spec, and 20 va Ives. 5 valves. I spec. 3 valves. 14 — 2 spec, and 4 ' yal ves. 8 — 2 valves. ca. 100 \-alves. 70 - 2 — LAMEIXIBRANCHIATA. 9 63°i772'N.Iy., I7''39'W.L 87 fin., lilack sand w. shells and stones. 3 spec, and i valve. 63°2i' — , i7°3i' — '^>9 - , black sand with shells. 2 — 63°2i' — , I7°i5' — 58 - , sand, stones and shell-gravel. 3 spec, and 25 valves. 63°24' — , 17° 5' — 70 - , black sand w. stones and .shells. 4 valves. 63°3o' — , 17° — 57 - 4 spec, (from stomach of cod). 63°2i' — , i6°22' — . . 263—295 - 2 — The largest specimen is 21"'"'; some are of the \arict\- aculrata. The Faeroes. Anoniia sqiiarnnla has been frequently taken at the Foeroes during recent years, from tlic shore down to a depth of 475 fin. The localities arc the following: Viderejde i valve. Svino 9 spec. Klaksvig 10 — 15 fni. 25 valves. — II - , on Laminaria. 32 spec. Arnefjord 0—15 - , hard bottom. 12 — Bordovig 7 — 10 - , black sand, small stones, Laminaria. ca. 100 valves. — 7 — 15 - ) sand with Laminaria. 2 spec. — 10 - 9 valves. Ejde 5~6 - , coarse, black sand. 72 — Fundingsfjord 12— ca. 20 - , coarse sand and clay. Some spec, and many valves. Andefjord 16 — 23 - 3 spec, (on Modiola modiolus). Solmunde , on Scrpitla tubes. 7 spec. Kongshavn 12 — 16 fm. 5 — Vestmanhavn 3'/2 - fine black sand. 8 valves. — 4-1 sand. I spec. — 4-5 - 2 — — 5—6 - , fine, black sand. 10 valve.s. — 10 — 30 - Some specimens and ca. 100 valves. Vestmansund ca. 70 - 8 valves. Sandevaag on Laminaria. 10 spec. Sorvaag 14— 16'/_, fm., mud. 6 valves. Midvaag 7 — 11 - 3 — Kalbakfjord 3 spec. Tliorshavn, outer harbour . . 12 — 16 fm. 3 — and 5 valves. Glivursntes at Thorshavn 2 — Nolso, beach 8 valves. — deep hole at north end, ca. 100 fm. Many spec, (on Modiola niodiolits). Sandsvaag , on Laminaria. 5 spec. Tile Ingolf-ExpeJition. IL >, 2 lO IvAMELUBRANCHIATA. Kvalbo Trangisvaag 6— 8fm., mud and clay. — 20 - , on Laminaria. 62°29'N.Iv., 7°37'W.L 60 - , sand and shells. 5 miles N. of east point of Myggeuses 5° - 7 miles N. by E. of east point of Myggenses 57 - 13 miles S. of Myggentesholm 70 - 6i°4o'N.L., 7°4o'W.L 135 - 6i°i5' - 9°35' - ca.475 - 61° 7' - 9°3o' 440 - 6i°o6' — 8°3o' 61 - 61° — 8°52' 90 - 6o°55' - 8°56' ca. 75 - 9 miles E. S. E. of Bispen . . . ca. 70 - 5 - S.S.E. - 50 - 6 — N. by W. of Kalso .... 60 - 1 1/2 — 2 miles off month of Bordo- vig 20—30 - Bordonaes in N. 75 W., is/^ miles . . 30 - 16 miles E. by S. of south point of Nolso 80 - Akralejte in N. 57 W. 12 miles. . 150 - 13 miles W. by S. of Munken ca. 150 - 6i°35'N.L., 4°39'W.Iy 210 - I valve. 4 — 40 spec. 7 — 80 valves. 3 — 2 — 19 spec, and 22 valves. 3 30 valve.s. - 67 - 2 spec. 4 — 20 — (on Balani). 12 valve.s. 3 — 12 spec. 27 — and 5 valves. 60 — (on Modiola viodinhis). 5 .spec, and 6 valves. 2 — — 7 — ca. 100 valves. 4 — The largest specimen measures 23.5 '"'". A number belong to the variety aculcafa. The specimens from the deep localities (210—475 fm.) are thiu-shclled and small (none over 11 "'"'.). The shells may also be very thin however in the littoral belt. Distribution. Anomia squaviula with the variety aculeata has its northern boundary in the "warm area" of the White Sea (Knipowitsch) and Murman Coast (Herzenstein). It is distributed along the whole of the Norwegian coast, from the shore down to 400 fm. (G. O. Sars), and goes through the Kattegat down to the northern part of the Great Belt and the Sound (C. G. Joh. Petersen). Towards the west it is distributed, as shown above, as far as the Foeroes and round the whole of Iceland. In the Zoological Museum of Copenhagen specimens occur on Cidaris papillafa spikes from the sea between Orkney and the Shetlands (135 fm.) and from 6o°39'N. L., 3°o9'W. L. (203 fm.) as also from many localities in the North Sea, down to a depth of 65 fm. It occurs on all the British coasts. Where the southern boundary of its distribution lies, I am unable to say, as the authors have confused this .species with the more southerly Anomia rphipphim (comp. 13.3). but it goes at least to the Bay of Biscay, where the Danish research-steamer "Tlior" has taken some specimens at great depths LAIMIU.I.IHRANCHIATA. II (43°37'N.L., 2°oS'W.L.; 250— 790 fm.). On the western side of the Atlantic it is distributed from Hatteras to the southernmost part of Lal^rador'). Ostreidae. Ostrea edulis I.inne. [I c e 1 a n d. | In "Brit. Conchol." vol. II, 1863, p. 40 Jeffreys gives Iceland as the northern boundary for the distribution of the oyster-) and Mohr as his authority. If we look up the work of the latter: "Forsog til en Islandsk Naturhistorie", 1786, we find Ostrea cdiiiis mentioned (p. 130), it is true, but with the addition, that it "is said to occur in Hvalfjorden" according to E. Olafsen. But in the work of Eggert Olafsen and Biarne Povelsen: -'Reise igjennem Island" (2nd part, 1772, p. loio) the record cited is followed by the remark "but we have not seen it." As no other naturalist has found the oyster at Iceland since that time, it may be deleted from the fauna. [The Faeroes.] From here the collection of the Zoological Museum possesses quite a small oyster (length 8"""., height 10 """.) attached to a shell of Modiola inod/oliis and still containing the dried-up soft parts; the specimen was sent in by Sysselmand IMiiller in 1873. So far as I know, this is the only evidence we have, that the oyster may occur at the FceroesJ). It is hardly credible, however, that adulf oysters occur at the islands, as they would scarcely have escaped attention. Nor can the small specimen referred to be considered to have been transported here as larva by oceanic currents, as no current runs from the English or other European coasts to the Fteroes-i). But experiments have perhaps at some time been made to "introduce" oysters at the Faeroes. Pectinidae. Pecten pusio Liune. Ostrea pusio I^iune, Syst. Nat. ed. 12, i, 2, 1767, p. 1146. — Pcctai pusio Jeffreys, Brit. Conchol. II, 1863, p. 51, PI. 22, fig. I. Pcctcn (Hinnitcs) disfortus Morch, Vidensk. Medd. naturhist. Forening 1867, p. 98. 1) In a geologically very late (.postglacial) period Anomia sqiiamiila was distributed to West Greenland, where it is now extinct; cf. Ad. S.Jensen: On the fossil quaternarj' Mollusc-Fauna of Greenland (Medd. oni Gronland, XXIX, 1909, p. 293); and Ad. S.Jensen and P. Harder: Post-glacial changes of climate in arctic regions as revealed by investigations on marine deposits (Postglaziale Klimaveranderungen, Stockholm 1910, p. 399). 2) The same statement is repeated in Proc. Zool. Society, 1879, p. 555. 3) In his "Fauuula Moll. Insul. Faroensium" (p. 99) Morch cites the following passage from Landt: "it (i.e. Anomia sgiiamula) is attached to small stones on the bottom at the same place as "the small oyster, Ostrea nu'nuta", which he has fished up from the bottom of Vestmanhavnsfjorden close to the Vaago side'' and adds to this: "what we are to vinderstand by Landt's Ostrea minuta is not clear; Landt has perhaps overlooked the hole in the shell of an Anomia, or he may even have meant a distorted Saxicava" . 4) The Fsroes are washed by the Gulf Stream, but it is improbable that the pelagic life of the oyster is of such long duration, that the larva could be carried the long distance across the Atlantic. Further, the specimen in question belongs to the European oyster (Ostrea edulis), as the muscular impression is white, not dark as in the American Ostrea virginica (cf. Whitea ve.s, Catal. of the marine Invertebrata of Eastern Canada, 1901, p. 116). 2* 12 LAMELLIBRANCHIATA. The "Ingolf has taken this species at: vSt. 87. West Iceland (Brede Bugt) no fm. i valve (height 4 """.). Fnrther, Pcctcii piisio has been taken dnring recent years at several places on Sonth-VVest and South Iceland, namely: S o u t li-W est Iceland: Brede Bugt, off Hellissandur ... 20 fni. Faxafjordr 17 -, coarse shell-sand. — mouth of Kollafjordr g'/a-ii - , fine black sand and mud. i fragment. Hafnarfjordr, i mile W.3/^N. of Hel- gasker Vager 1472 fm. i spec. Skagi 21 - 2 valves. 1 valve (small). 10 — — South Iceland: Grindavik Vestmannaeyjar 10 — 20 fm. I valve. I spec, and i valve. 30 - , gravel with many shells. 4 valves. 49 - . clay. Heimaey shore. Numerous valves. 17 valves. The largest specimens are from the A'estmannaeyjar and measure: length 30 """., height 35 "'"'. — 33-5- — 36 - The largest specimen from the west coast (that from Hafnarfjordr, 1472 fm-) measures: length 15 "'"'., height 18.5 """. The fragment from Faxafjordr, g'/a — n fm., however, has been of considerably larger dimensions. The Faeroes. When Morch wrote his "Faunula Molluscoruni Insulanim Fteroensium" he knew a specimen and a valve from the Fasroes, but the locality is not stated; the specimen, which contains the remains of the soft parts, is 32 nun. high and 27 nun. long; the valve is 38 mm. high. In recent years Pcctcn pnsio has been taken with the dredge at the following places: Ejde 5 — 6 fm., coarse, black sand. Vestmanhavn 10 — 30 - Nolso, deep hole at north end ca. 100 - 7 miles N. by E. of east point of Myggen9es 57 - 5 miles N. of east jwint of Myggenses 50 - 13 miles W. by S. of Mnnken ca. 150 - Foeroe Bank 58 - 1 valve (small). 2 — 2 — I — I — 4 — I I.AMELLIBRANCHIATA. 1 3 The largest of these valves is 36 '""'. liigli and 26 """. long-. AiuDiig the specimens from Iceland are some down to a size of scarcely 2 """. The prodis- soconch is smooth; immediately under it are radiating ribs, which are more or less spinous and tuberculous. Small specimens are difficult to recognize as belonging to this species, as they are relatively elongated, with the two dimensions of the shell almost the same, and the ears extremely well- developed; they might easily be confused, for example, with the young of Prctot varins. Medium- sized specimens still free are higher than long and of regular form. I^ater, the growth becomes irregular owing to the sedentary mode of life. Distribution. In addition to South-West and South Iceland and the Faeroes, P. pusio occurs at Southern Norway, but it has not been found living in the Danish waters inside the vSkaw (a few dead, probably fossil, valves have been taken in the Eastern Kattegat). It also occurs at the British coasts ("on every rocky coast from Shetland to Cornwall"), along the coast of France and the Liberiau Peninsula, through the whole of the Mediterranean right to Asia Minor. It is further distributed as far as INIadeira, Canary Isles, Azores and Liberia, according to Dunker even to the Cape of Good Hope. The vertical distribution extends at Norway from o to go fm., according to G. O. vSars, and at the I.ritish Isles from o to 85 fm., according to Jeffreys. Nevertheless, the latter author records the species as taken by the "Lightning" N. of the Hebrides in 530 fm. and b}- the "Porcupine" off the west coast of Ireland in 808 fm. Other authors also record it from great depths, thus Dautzenberg and Fischer') from 1360m. and 1494 m. at the Azores, and A. Locard-) from 896— 2285m. in the Bay of Biscay and north coast of Spain, as also from 1200 m. W. of the Soudan. Is it not possible that these records are based on mistakes? Or were they only dead shells which occurred at the great depths? Remarks. Pcctcn piisio is here taken sciisu latiorc. The French malacologist A. Locard defin- itely maintains that the -P-piesio" of the authors covers two distinct species, namely: (i) a free-living species for the whole of its life, of regular form (Pcctcn iiiultistriatus Poll); (2) a species permanently attached in adult condition, always of irregular form (P.distortus da Costa); the first species belongs to the Mediterranean, though exceptionally occurring in the Atlantic as far as the Bay of Biscay and coast of Liberia, whereas the latter species is exclusively an oceanic form, with a distribution from the Azores to Norway J). It seems to me, however, that Lo card's mode of reasoning is not conclusive in the matter. Bucquoy, Dautzenberg and Dollfus seem likewise most inclined to consider P. distortiis and P. vniltistriatus as one and the same species, inter alia^ because both forms ma\- be found as members of the same "colony" and thus in all probability of the same origin. 4) Pecten opercularis Linnc. Ostrca opercularis Linnc, vSyst. Nat. ed. 12, i, 2, 1767, p. 1147. — Pcctrii opercularis Jeffreys, Brit. Conch. II, 1863, p. 59, PL 22, fig. 3. Pcctcn opercularis Morch, Vidensk. Medd. Naturhist. Foren. 1867, p. 98. 1) Mem. Soc. Zool. de France, X, 1897, p. 193. 2) Exped. scient. Travailleur-Talisuiau, Moll. Test. II, 189S, p. 379. j) A. Locard: Contrib. a la fauiie nialacol. P'ran(;aisc. XI Monographic. Pecten, 188S, p. 38; idem: Exped, .scient. Travailleur-Talisman, Moll. Test. II, 1898, p. 377—79- 4) MoUusques marins du Roussillou, II, 18S7— 98, p. 106. J. LAMELLIBRANCHIATA. The Faeroes: M or ell's list gives this species from Kollefjord (on Stroiiio)") and from "Fiskebanken" W. of the Faeroes. In recent years Pccten opcrcjilaris has been dredged at the following places: Klaksvig 10—15 f'"- i valve. Andefjord 16—23 - i — Fnndingsfjord 12 — ca. 20 - , coarse sand and cla}'. i spec. & 5 valves. Ejde 5 — 6 - , coarse black sand. 2 \alves. Vestmanhavn 5— 6 - , fine black sand. i spec. 5 — 13 - mud and black sand. i — — 10—30 - I valve. Nolso, deep hole at north end ca. 100 - 2 spec. & i valve. Trangisvaag i — 12 - i spec. 62°29' N.L., 7°37'W. L 60 - , sand and shells. i valve & i fragment. 62° 16.5' — , 6°6' — 50 — 60 - 10 valves. 62° 1 6 — , 5°54' — 50—60 - I valve. 5 miles N. of east jjoint of Myggemes 50 - 2 fragments. 7 — N. by E. of east point of Myggenses 57 - 9 valves. 61 "56' N.Iy., 7'04'W. L 30 - I valve. 61^40' — 7°4o' — 135 - I — 61° — 8°52' — 90 - 2 spec, and i valve. 6o°55' — 8°56' — 69 - 4 valves and some fragments. 9 miles V^. S. E. of Bispen .... ca. 70 - 3 valves. 6 — N. by W. of Kalso . . 60 - 7 spec. I'/a — 2 miles off mouth ofBor- dovig 20 — 30 - I .spec, and i valve. 16 miles E. by S. of south point of Nolso ca. 80 - 4 spec. 13 miles W. by S. of Munken - 150 - 7 valves. It should be emphasized, that all the specimens taken in the fjords and at the coast itself are small, at most 24.5 """. In the open sea round about the F^aerocs, on the contrary, many large indiv- iduals have been taken; the largest living specimen measures 65"""., the largest of the empty shells So™"'. The specimens vary somewhat in regard to colour and sculpture, just as at other places. Distribution. Pccten opcrcularis occurs at the Canary Isles, Madeira and the Azores. It is common in the Mediterranean (including the Aegean) and along the coasts of Europe to Southern ■) It is probably these .specimeu,s (collected by lap. Steenst rup) to which Jeffreys refers, when he writes (I.e. p. 60): "Steenstrup informs me that he has found it (P. operadaris) in IceLnnl'', the Fteroese locality being confused with KoUafjordr in Iceland. Pccten opcrcularis has never been found at Iceland. LAMELLIBRANCHIATA. 15 Norway; its iiortheni boundary, according- to Sjjarre Schneider, is reached in Norway at 6y°'N.J^. It enters the Kattegat, in the southern part of which it is connnon, as also into the Sound to the isUind Hveen. In the west, as shown above, it ranges to the Faeroes. Jeffreys estimates tlie vertical distribution of the species at o — 180 fni., and at Norway accor- ding to Sars, it only goes down to 100 fni. and at the Faeroes to 100 (150?) fm. Nevertheless, Jeffreys states that ihe "Lightning" and "Porcupine" Expcd. have taken it N. of the Hebrides at 530 fm., W. of Ireland at 808 fm. and off the Channel at 257— 690 fm., as well as off Portugal at 364 fm., but it is not stated whether these were living specimens or empty shells; from the Azores also it is given by Fischer and Dautzenberg from a depth of 1360m. Pecten island icus Miiller. PI. I, fig.s. 4 a — b and c — d (youngl Pccttii islaiidicus Miiller, Zool. Dan. Prodrom., 1776, p. 248; Sars, Moll. Reg. Arct. Norv., 1S78, p. 16, PI. 2, fig. 2; Verrill, Trans. Conn. Acad., X, 1899, p. 72, PI. XVI, figs. 2 — 5. — Pecten Fabricii Philippi, Abb. u. Beschreib. neuer oder wenig gekaunter Conchyl., I, 1845, P- ^o^! Pecten Tab. I, fig. 5. Pecten islai/dicus Fabricius, Fauna groenl., 1780, p. 415; Moller, Index Moll. Groenl., 1842, p. i6; Morch, Rink's Gronland, 1857, p. 94; Vidensk. Medd. Naturh. Foren. 1868, p. 225; Arctic Manual, 1875, P- 133; Rink's Dan. Greenland, 1877, p. 442; Becher, Osterr. Polarstat. Jan INIaycn III, 1886, p. 68; Posselt, Medd. om Gronland, XXIII, 1898, 1x14. This species has been taken by the Ingolf-Expedition at the following places: St. 31. Davis Strait 88 fm. i°6 C. i spec, (small). - 26. — — 34 - o°6 - I — - 127. N. of Iceland 44 - 5°6 - 4 valves (i with remains of soft parts). - 87. W. - — (Brede Bugt). . no - 2 — , ancient in appearance. - 86. — - — — — .. 76- I small spec, and several valves, ancient in appearance. 6. E. - -- 90 - 7°6 - I young spec. West Greenland. Ver\' common from the soirthernmost parts and as far north as zoological investigations have been made, namely to Ivsugigsok (76° N. L,.). The largest specimen I have seen is from Egedesminde and measures 105"'"'. It occurs most frequently at depths of 15 — 50 fm. and prefers hard bottom. At some of the colonies (Holsten.sborg, Egedesminde) the Danes frequently send out men to dredge for it on the "banks", where it flourishes in quantity, especially when they have guests to whom they wish to offer this Greenland delicacy; its large adductor muscle has a very good taste and it even seemed to the malacologist H. P. C. Moller "more tender and finer in the flesh than Ostrea edulis'\ The same author states, in a manuscri]-)!, that /-". islaudiciis "moves very rapidly by firm beats of the valves and can thus spring almost a foot each time; I have never seen it use the foot". i6 LAMELLIBRANCHIATA. East Greenland. Whole valves, still less living specimens, have not been found; on the other hand, some fragments have been taken in the dredge off Angmagsalik in 140 fni. (a fragment) and in Forsblads Fjord in 50 — 90 fm. (fragments of a larger and a smaller valve). I^'urthcr, a shell fragment has been found at Rolige Brae in the inner part of Scoresb}' Sound M. Jan Mayen. The Austrian Expedition of 1882 — 83 found numerous specimens on the north side of the island, 75 — 95 fm. The Danish Expedition of 1900 obtained 9 living specimens and various valves on muddy bottom at a depth of 55 fm.; the largest was 86""" in height. Iceland. Pfc/ni islaiidiciis has not been found at all on the south coast but it is common on the other coasts of the island. The specimens, which are preserved in the Zoological Museum, come from the following localities : East Iceland: 64°27'N. L., i3°27'W. Iv 84 fm. i valve (fo.s.sil perhaps). 64°58' - , i3°25' - 40 - I - Fa.skrudsfj6rdr 50—20 - 3 spec, (small). Outer Reydarfjordr 60 — 80 - 2 — Reydarfjordr 86 - i — Nordfjordrs Floin 35 — 55 - i — Mjofifjordr 40 — 52 - i — Seydisfjordr 10 - i — — at Skulavig 6 - i — Bakkafjordr 20—28 - i — — 25-32 - 10 — — 52—43 - " -- (small) The largest sjiecimen is 78""" high. North Iceland: Haganesvik 3'/^ — 4 fm. 3 valves. Axafjordr 22 - 3 spec. — 30 - 2 valves. Ofjord 2 — 3 - I spec. — II - 2 — 66°i7'N.L., i8°i3'W.L 52 - i — Kollafjordr 5- i — 10 - I — & 3 valves. Veidileysafjordr 21 — 25 - 3 — ') Cf. A J. S. Jensen, Mcdil. oni Gronland, XXIX, 1909, pp. 301—2 and 333. LAMELLIBRANCHIATA. 17 It is naturally due to chance that all the shells brought home are small in size, none over 60"'"'; in reality very large specimens occur at North Iceland and in extremely large quantities at places. Hesteyrarfjordr 15 — 171/2 fm. Dyrafjordr, inside Thingnses 10 — la'/a - . — 18 - — 20 - Bildudalr 5 — 7 - Fossfjordr 44 - Talknafjordr 14 - — ca. 24 - N.W. of Talkni Patreksfjordr drag-net on beach 65° 1 7.5' NX., 23°24'W.L 28 fm. Hvalfjordr 24 - Faxafjordr, Keflavik 15 — 16 - — , ca. 2 miles N.E. of Kefla- vik ig'/j — 20';'2 - — , ca. 3 miles N. 59 W. of Grotta Light 25 - Reykjavik Roads — — near Engey — , Engey l—^iz - Hafnarfjordr 4 — 7 - — , I mile E.N.E. of Helga- sker Vager 11' , - • — , I mile W.V4N. of Helga- sker Vager i4'/2 - West Iceland: mud aiul small stones. fine, black sand. 2 spec. 15 valves. 7 spec. I ■— I — 2 valves. 10 spec. I — I — & 2 V •alves, I — 3 — Several spec. I fragment. ooze. I valve. I spec. I — ooze. bottom-temp. 9.3° C. (August). 6 Even at the southern boundary of its occurrence at Iceland the species attains a considerable size; the specimens from Hvalfjordr reach a size of up to 80""", from Reykjavik up to 95"" and from Hafnarfjordr up to 78"'™. Outside the fjords however, it has not been taken further south than in Brede Bugt, and the living specimens from there are only 20 — 25"'"'. [The Faeroes.] In recent vears a number of shells of P. islandicus, all large (72 — 90 "'"j and with a "fossilized" appear- ance, have been taken with the dredge at various places out to sea round about the islands, namely: S. of Myggenses from the line-fishing i valve Akralejte in X.57W. 12 miles 150 fm. 3 — , fragments. 6i°io' N.L., 5'46' W.L 150—160 - i — 6i°2i' N.L., 5°i2' W.L 210 - I — The Ingolf-Expedition. II. S- 3 i8 LAMELLIBRANCHIATA. As no living specimens were forthcoming, it may probably be taken as fairly certain, that Pecten islandicns no longer lives at the islands. Remarks. The radiating ribs of the shell begin to appear in the young immediately below the prodissoconch. In the beginning the shell is provided with very dense, concentric lines (PI. I, fio-s. 4 c and d), which in the spaces between the longitudinal ribs give way later to a very characteristic rasp-like structure (distinct under the lens) (PI. I, fig. 4 a). The longitudinal ribs themselves are often smooth, but not rarely rough from down-turned spines or scales. The rasp-like sculpture is almost always present, if the shell is not too much rubbed; it may be difficult to see or has disappeared only in the cases, when the radiating ribs lie very closely and are covered with scales, but even on such specimens it can as a rule be observed on the older parts of the shell (PL I, fig. 4b). Curiously enough authors do not seem to have attached any weight to this good distinguishing character, and Verrill has even recently established a special variety iiisciilpfa (1. c, p. 73, fig. 5) for specimens with such structure; in my experience this is practically never wanting, when carefully sought for under a lens. Some few of the Greenland and Iceland specimens belong to the variety, which Chemnitz has described and figured in Conchyl. Cabinet VII, 1784, p. 318, Tab. 65, fig. 616: the shell is thrown into undulating, radial folds. I have also a similar variety from Jan Mayen. Distribution. Pcctcii islandicits is an arctic species, but whether it is circurapolar, as is generally stated, seems to me more than doubtful. It has been taken, it is true, at Labrador, West Greenland, Iceland and Spitzbergen, in the Barents Sea and at the entrance to the Kara Sea, but it has not been found in the Kara Sea nor in the Polar Sea of Siberia'); then it appears again in the Bering Sea, but it has not been met with in the Polar Sea north of arctic America 2), any more than at the high-arctic East Greenland. In the Atlantic to the south it reaches to Cape Cod and West Norway 3), in the Pacific to Korea and North Japan 4). — Its vertical distribution extends in general from 5 to 50 fathoms, but sometimes it goes deeper down. Shells ancient in appearance have been taken at many places, where it is certain the species no longer lives, e. g. at Bohuslan (Malm), in the Kattegat (C. G. Job. Petersen), in the North Sea (Metzgeri, at the British coasts (Forbes &: Hanley) and off the west coast of Ireland ("Porcupine"). I) The Dijmphna-Exped., whicli made many dredgings in the Kara Sea, only got a single small specimen, and it was not taken in the Kara Sea itself, but in the entrance (Jugor Strait). Nor was it found by the Vega-Exped. in the Polar Sea of Siberia. -) Under the distribution of P. islainiiciis, Posselt (1. c, p. 15) notes "Wellington Channel" and Belcher as his authority. But on looking up Belcher: "The last of the Arctic voyages" (1S55), where P. islandicus is certainly noted among the Molluscs collected by the Expedition and determined by Lovell Reeve (Vol. II, p. 396), we find the locality given as "Lievely, Greenland'', i. e. Godhavn on Disko Isl. in W. Greenland, which was touched at by the Expedition both on the outward and homeward voyage. "Lievely" is the name given by the English whalers to Godhavn. 3) The southern boundary lies right down about 59°N.L., where Dr. O. Nordgaard in 1902 took a specimen off the mouth of Lysefjord (Bergens Museums Aarbog 1903, No. 8, p. 36); Dr. Nordgaard kindly permitted me to see this specimen, which was 45 mm. high and taken at a depth of ca. 24 fm. At Bergen already, where M. Sars found it, though only as small, dwarf-like specimens (50mm. high), P. is/aiidicus is rare, as it is not mentioned in Friele's or Norman's lists of the MoUuscan fauna of Bergen Fjord. I have had the opportunity of seeing two specimens from the immediate neighbourhood of Bergen, taken by Dr. Nord gaard, the one in Radosund at a depth of ca. 5ofm. (height of specimen 29.5 mm.), the other, of the same size, in Alvaerstrommen at a depth of i6 fm. along with Pecten opercularis. 4) From Engineer Schonau of the Great Northern Telegraph Co., our Museum has received a specimen from tlie coast of Korea and one from the waters S. of Wladiwostock (42°I5'N. L., 130=43' E.L..). LAMELLIBRANCHIATA. 19 Nor can I believe, that the shells of this species stated to have been taken off the west coast of France, 748—1262™. ("Princesse Alice") and in the Bay of Biscay, 400 m. ("Caudan") were "fresh" — nnfortunately, the authors say nothing as to the condition of the shells — though Locard makes the following statement regarding P.islandicns : "C'est, comme on le sait, une espece particulierement septentrionale, qui ne vient jusque dans nos regions qu'a la condition de se propager en eaux profoudes".') Pecteti islandiats is not a particularly high-arctic species; it lives in greatest quantity, forming whole banks of shells, at Finmarken, North Iceland and South-West Greenland as well as on the fishing banks of Nova Scotia and Newfoundland, whereas it occurs much more sparsely at Spitzbergen ^). Morch also remarks, that it does not grow so large in the high norths). As mentioned, it attains a considerable size even so far south as S. W. Iceland, where the bottom-temperature in August amounted to 9.3° C. Pecten aratus Gmelin. PI. I, figs. 5a — e. Pecten arafns Gmelin, Linn. Syst. Nat. ed. 13, 17S8, p. 3327. Pecten silica t us Jeffreys, Brit. Conchol. II, 1863, p. 64; Proc. Zool. Soc, 1879, p. 557 Norv. 1878, p. 17, Tab. 2, fig. 3. The "Ingolf Expedition has taken this species at: St. 98. W. of Iceland 138 fm. - 97- - - - - 89. - - - - 9. S.W. - — - 10. - - — - 85. - - - - 55-S.E.- - Pcctoi aratus Sars, Moll. Reg. Arct. 138 fm. 5.9° c. A number of valves. 450 - 5-5° - I right valve. 310 - 8.4^ - I spec. &: I left valve. 295 - 5-8° - II valves. 788 - 3-5° - I small spec, (height 6""" 170 - 2 valves. 316 - 5-9° - 2 spec. At Iceland and the Faeroes — where it has not been known hitherto — it has also been taken at the following places by Danish expeditions: 64=42' N.L., 27°43' W.L 426 fm. 6' C. 63=15' — 22^^23' - 170-114 - 20°7' — 293 - 2o"o6' — 268 - 9°35' — ca. 475 - 63=05' - 63=12.5' 61=15' I spec. 1 — 2 — & 13 valves, ca. 20 spec. I spec. The specimens to hand are rather variable both in form and sculpture. As a rule the height is somewhat greater than the length, but the two dimensions may be almost equal. In consequence of this the circumference is variable, the lower contour forming sometimes a part of an oblique oval, some- times an almost perfect arc of a circle. The number of the primary, stronger ribs is extremely variable 1) Campagne du "Caudan", par R. Koehler, 1S96, p. 207. 2) Torell: Spitsbergens MoUuskfauna, 1S59, p. 124. 3) Catal. des Moll, du Spiteberg, p. 27. .\nn. Soc. Mai. de Belgique, IV, 1869. 3* 2Q LAMELLIBRANCHIATA. e. o^. 6, 8 (PI. I, figs. 5a & b), 10 and 12. Sometimes the intermediate ribs are almost as well developed as the primary, so that the difference is not appreciable, and the sculptnre then assumes a certain res- emblance to that in Pecten islandicus; it lacks however the characteristic intercostal, rasp-like structure of the latter (PI. I, figs. 5 c & d). Each primary rib again is composed of a varying number of small ribs, which may be smooth but are usually rough (at least towards the periphery) from the presence of small, erect scales (PL i, fig. 5e). All the specimens to hand are grayish-yellow to straw- or orange- yellow (elsewhere the colour is described as purple-red or rose-red). The largest specimens measured: Length Height Breadth 29.5™™ OQ mm jr' 29.5 - 29.5 - 8 28.5 - 29 - 7 24.5 - 27 - 7 ■ mm Distribution. Pecten aratits ranges from Morea through the Mediterranean to the Atlantic off Soudan ("Talisman"), Pyrenean Peninsula, France and Ireland, as also north of vShetland'); further, it occurs from Bohuslan along the coast of Norway to Lofoten ^). Lastly, the Danish investigations have shown that it goes south of the P"seroes and south of Iceland and a good way up into the Denmark Strait. Its vertical distribution is placed by Jeffreys at from 20 to 530 fm.; the "Ingolf" however has taken a living (though small) specimen at a depth of even 788 fm. (St. 10). Among the synonyms of this species Jeffreys gives Pecten briiei Payraudeau, but French and Italian authors do not agree with him here. After examining a specimen of P. brnei (from Corsica) sent to our Zoological Museum by ^larchese di Monterosato, I consider there is no doubt, that Jeffreys is right; this means at the same time that P.aratus is distributed in the Mediterranean. Pecten septemradiatus Miiller. PI. I, figs. 6a — -c [\2iX. scaber). Ostrea septemradiata Miiller, Zool. Dan. Prodr., 1776, p. 248. — Pecten septemradiatus Jeffreys, Brit. Conchol. II, 1863, p. 62, PI. 23, fig. i. This species has been taken by the "Ingolf" at the following stations: W. of Iceland 138 fm. 5.9" C. Fragments of numerous valves. St. 98. - 89, - 9 - 8. - 85. - 55' - 6. S.W. S. E. - - N. W. of the Faeroes i ?2 - 310 - 8.4= - I spec. 295 - 5-8°- I spec, and 8 valves. 136 - 6.0° - Fragments of 4 — 170 - — - 7 — 316 - 5-9° - I spec. 90 - 7.0° - 2 valves. 132 - 7-2° - 7 spec. ■) During mj- participation in the cruise of the "Michael Sars'' in 1902, I obtained a specimen at 6o°2:.5' N. L-, 3° 55'W.L., 148 fm. 2) Neman's record of its occurrence right up at 71° i2'3o" N.L., 20°3o'3o" E.L., 135 fm. seems hardly credible and is based in all probabihty on an erroneous determination (Niederland. Arch. f. Zoologie, Suppl. Bd. i, 1S81 — 83, No. 10 p. 3). LAMELLIBRANCHIATA. 21 In recent years, further, it has been taken at other places at Iceland and the Fseroes, namely: Iceland. 63=15' N.L., 22'23'W.L 170-114 fm. 63°i8' - 2i°3o' - 94 - 63°o5' 20°o7' - 293 - 63° 1 2.5'— 20°06' 268 - Faeroes. 62-29' N.L., 5' 17 61^40' — 6i°i5' - 6i°09' — 61^07' — 61 "06' - 740' 9°35 7 '54' 9'3o' 921 W. L. . . . 191 fm. ••• 135 - ca. 475 - . . . 180 - . .. 440 - . . . 210 - Akralejte in N. 57 W. 12 miles ca. 150 13 miles W. by S. of Munken - 150 2 spec, and 23 valves. I fragment. II valves. 1 valve. 2 valves. ca. 25 valves. 3 valves. 2 spec, and 5 valves. I valve. I — 9 spec. &. numerous valves. I valve. Pecicn semptemradiaUis is thus quite common round the Faeroes and the south and south-west of Iceland, which has not been known hitherto. It does not enter the fjords, however, occurring only in the open sea. It has been taken at depths of 90—475 fm. (living specimens however only from 132 — 316 fm.). The specimens to hand from Iceland and the Faeroes show no small variation with regard to the sculpture of the shells. Compared with typical specimens (from the Kattegat) they liave on the whole more numerous folds (8—13) (PI. I, figs. 6 a — b) and are very distinctly radially striated on the left shell. Some specimens are smooth, in others again the radiating stripes of the left shell are rough from the presence of small, down-turned scales; lastly, the specimens from stations 9 and 89 of the "Ingolf have not only the stripes on the left valve densely beset with such sharp scales (PI. I, fig. 6 c), but likewise have the stripes which lie between the radiating folds of the right valve provided with small spines. Had transitions not been present, one might have been tempted to consider the last- named specimens as belonging to an independent species; it will now be most correct to call this, the most strongly spined form, by the name of var. scaber. At the Fseroes and Iceland the species attains to a considerable size; the largest specimens measure: lyength 55 "^"> Height 52 ™™ Breadth 13 """ — 55 - — 55 - — 13-5 - Distribution. According to Locard') Pecten scptoiiradiatus does not live in the jMediterrauean, but is an oceanic species occurring off West Africa (Sahara), at the Canaries, the French Atlantic coast and in the Channel. At the northern parts of the British Isles, as also in the southern Skager Rak I) A. Locard: Contrib. a la faune malacol. fran(;aise, XI, Mouogr. Pecten, 18SS, p. 90; idem: Res. scient. de la camp, du "Caudan", 1896, p. 211. English authors are said to have confused with P. septemradiatus the more southerly P. clavatits Poli (^ P. inflexa Poll; P. Dumasti Payraudeau). Cf. also Bucquoy, Dautzenberg et Dollfus: Les Moll, marins du Roussillon, II, 1887 — 98, pp. 69 — 70; cf. also, however, the record of the occurrence of P. septemradiatus at Bouches du Rhone, p. 802. 23 LAMBLUBRANCHIATA. and in the eastern Kattegat (its southern boundary lies in the Sound at Hveen Island). Further it is very common along the Norwegian coast, right up to Varanger Fjord (7o°N.L.) and, as shown above, our knowledge of its distribution has been extended to embrace also the Atlantic at the Fseroes and at south and south-west Iceland. — The bathymetric distribution extends from 15 to over 300 fm. M. Sars considered P. septemradiatus [P. daniacs Q.\i^va.n.) as an arctic species'), and G. O. Sars inclines to the same view, as his father has found the same species very common in the fossil con- dition in the older glacial marl. As will have been seen from the above list, the "Ingolf has only taken this bivalve at localities with fairly high temperature; nor has the species been found elsewhere, where the conditions are "arctic" in the hydrographical sense of the word. As it is inconceivable, that the above authors could have made an erroneous determination of this easily recognized species, I venture to conclude that P. scptcniradiahts belongs to a layer, which has been deposited under milder climatic conditions. I notice also, that W. C. Brogger has put forward quite the same view. He writes namely 2): "When we see, what a considerable size this species attains to in the Isocardia- clay (up to more than 62""'), there is no reason for believing it to be originally an arctic species, the less so, as it does not occur at all in the living or fossil, high arctic fauna. It is therefore undoubt- edly a typicalh' boreal species". Pecten tigrinus Miiller. Pecten figfejrimcs Miiller, Zool. Dan. II, 1788, p.26, Tab.6o, figs.6— 8; Jeffreys, Brit. Conchol. II, 1863, p. 65, PI. 23, fig. 2. Pecten tigerinus Morch, Vidensk. Meddel. Naturh. Foren. 1868, p. 226 and p. 229. The "Ingolf has taken this species at: St. 86. W. of Iceland (Brede Bugt) 76 fm. 9 valves (fragments). Iceland. Jeffreys gives "Iceland" as the home of this pretty species, as also Morch, who mentions Tor ell as his authority. In addition to the above locality from the "Ingolf, P. tigrimis has been taken in recent years at the following places at South Iceland: 63°i5'N.L., 22°23'W.L 170— ii4fm. i valve. 63°3o' — ' 20^14' — 42 - I — Vestmannaeyjar 30 - , gravel wath shells. 3 — — 49-5 clay with a little mud. 5 — 63°2i'N.L., i7°3i'W.L 69 - , black sand. 2 - 63°2i' — , I7°i5' — 58 - - sand, stones, shell-gravel. 15 — 63°24' — 5 17° 5' — 70 - ) black sand w. stones and shells, i spec, and 9 valves. The largest of these shells measures: length 21.5"", height 22 mm ') M. Sars: Fossile Dyrelevninger fra Quartserperioden, 1865, p. 127. 2) W. C. Brogger: Om de senglaciale og postglaciale uivaforandriuger i Kristianiafeltet, 1900- igor, p. 469. LAMELLIBRANCHIATA. 23 Faeroes. In an appendix to "Fannnla Moll. Insnl. Fteroensinm" Morch (1. c.l lias added P. tigrinus to the faiina of the islands, without however stating the locality. In recent years it has been taken at many places round the islands at depths of 20 — 150 fni., as will appear from the following list: \'estmanhavn 10 — 30 fm. i valve. Nolso, deep hole at north end ca. 100 - i spec, and i valve. 62°29'N.L., 7=37' W.L 60 - 2 valves. 62"i6' — , 5^54' - 50- 60 - 5 - 5 miles N.E. of east point of Myggenses . . 50 - 2 — 7 — N.byE.- - - - — ca. 57 - i — 13 — S. of Myggenassholm ca. 70 - 28 — 6i''4o' N.L., 7^40' W.Iv 135 - 6 — 6i°o6' - , 8'3o' — 61 - 2 — 6o°55' - , 8°56' - 69 - I - 5 miles S. S. E. of Bispen 50 - i — 9 — E. S. E. - — ca. 70 - 22 — 6 — N. byW. - Kalso 60 - 2 1 1/2 — 2 miles off mouth of Bordovig. . . 20—30 - i spec. 16 miles E.byS. of S. point of Nolso . . ca. 80 - 4 valves. Akralejte in N.57W. 12 miles ca. 150 - i spec, and 10 valves. 13 miles \V. by S. of Munken ca. 150 - i — - 9° — The largest of these shells measures: length 32""., height 31.5""'. These shells from Iceland and the Faeroes vary greatly in regard to form, sculpture and colour. Forbes and Hanley have given the following description which agrees well with our shells: "Some- times the surface is otherwise smooth, sometimes there is a marginal belt of narrow and very closely disposed depressed radiating costellse; occasionally these latter extend over the whole shell with or without the presence of about five principal radiating ribs, which are rounded, generally broad, and variable in amount of elevation (var. costata Jeffreys)".') In the last variety the margin of the shell is sometimes inflexed. Distribution. P. tigrimis is distributed along the west coast of Europe from the north of Spain to West Finmarken, also over the Faeroes to South and South-West Iceland; it goes further into the Kattegat. The vertical distribution is given by Jeffreys as 5 — 180 fm. Remarks on P. tigrinus and P. stria tus. Pecten tigri7Uis and P. striates are as a rule most readily distinguished from one another by the hindmost ears in the former being almost rudimentary, but well-developed in the latter; further, the radiating ribs in P. striates are beset with short vaulted spines or prickles, whereas these are lacking in P. tigrinus. Sometimes, however, it is not at all easy to separate them, as the posterior I) Forbes and Hanley: A history of British MoUusca, II, 1853, p. 286. 2A LAMELUBRANCHIATA. ears in P. tigrinus may be fairly large, and the hindmost part of the shell may show a trace of being echinated; on the other hand, the number of the spined ribs in P.striahis may be limited to two, even to one along the anterior edge of the shell, whilst the whole of the remaining part of the shell in form and sculpture agrees with P. tigrinus. Pecten striatus Miiller. Pecten siriatus Miiller, Zool. Dan. II, 1788, p. 26, Tab. 60, figs. 3 — 5; Jeffreys Brit.Conchol.il, 1863, p. 69, PI. 23, fig. 4. Pecten striatus Morch, Vidensk. Meddel. Naturh. Foren. 1867, p. 98. At Iceland the "Ingolf Expedition took this fragile .species at: St. 98. W. of Iceland (Brede Bugt) 138 fm. 5.9° C. 4 valves. - 86. - - — — — 76 - 8 — - 87. - - — — — no - 6. S. S. E. of — 90 - - 51- - - - 68 - 3 - 7"C. 3 spec. & I valve. 7-32^ - I — - I — places: I spec, and 12 valves. 3 valves. I valve. It has later been taken at Iceland at the following places: 63°i5'N.L., 22°23'W.L 170— ii4fm. 63=21' - 17=31' - 69 - 63°2i' - i7°i5' - 58 - The largest of these shells is 20 """. high. At the Faeroes, where it had already been noted by Morch, P. striatus has been taken at the following places: Thorshavn, outer roads 12 — 16 fm. i valve. Nolso, deep hole at north end ca. 100 - i spec. 6i°4o'N.L., 7='4o'W.L 135 - i valve. 16 miles E. by S. of south point of Nolso - 80 - 7 spec, and i valve. Akralejte in N. 57W., 12 miles - 150 - 5 valves. 13 miles W. by S. of Munken - 150 - 3 — The largest of these shells is 22.5 ™™. high. Distribution. P. striatus occurs in the Western Mediterranean (from Sicily) and ranges along the west of Europe to West Finmarkeu in Norway; it goes over the Faeroes to South and South- West Iceland'). It enters the Kattegat as far as Hellebsek and Samso. The vertical distribution is given by Jeffreys to be from 5 to 180 fm. Regarding its relation to P. tigrinus, see notes under the latter. ') The record given by Becher, that the Austrian Expedition has taken the species on the north side of Jan Ma)-en, 140-180 m. (Osterr. Polarstat. Jan Mayen, 1S86, III, p. 68) is undoubtedly based on an erroneous determination. I.AMia.LI BRANCH I ATA. ^5 Pecten imbrifer Ivoven. ri. II, fig. I \\-ar. »ia/or) &. fig. 2 {vav. i////ior). Pecten imbrifer Loven, Index Moll. Scaiid., 1846, p. 31; Dall, I>ull. Mus. Coiiip. Zool. Harvard Coll. XII 1886, p. 220, PI. IV, fig. 4; Friele & Grieg, Norvv. North-Atlantic Exped., Mollnsca III, 1901, p. 8. — Prcfen mamillatus M. Sar.s, Chri.st. \'id. vSelsk. Forh. 1873, p. 12. — Pcclcii HoskyiisiV^. O. vSars, j\Ioll. Reg. Arct. Norv., 1878, p. 20, PI. 2, fig. i ; var. major Leche, K. Sv. Voten.sk. Akad. Handl. 16, No. 2, 1878, p. 35; Collin, Dijmphna-Togtets zool.-bot. Udbytte, 1886, p. 453; \ar. pitstiilostis Verrill, Trans. Conn. Acad. V, 1882, p. 581, PI.42, fig. 22. — Cyclopectcn pustiilnsus V^errill, Trans. Conn. Acad.X, 1899, p. 70, fig. i &: p. 83, PL 19, fig-s. 3, 4; Verrill & Bush, Proc. Unit. Stat. Nat. i\Ins. XX, 1898, p. 839, PI. 85, figs. 5, 6, 10, 11. — Cyclopccfen stibimbrifrr Verrill & Rush, Trans. Conn. Acad. X, 1899, p. 84; Proc. Unit. vStat. Nat. Mus. XX, 1898, p. 840, PI. 85, figs. 8, 9. — Prcfen lucidus Noniann, Niederland. Arch. f. Zool., Suppl. Bd. I, 1881—82, No. 10, p. 2, PL I, figs. 5, 6, 7, 8. Pecten Hoskynsi Friele, Nyt Mag. f. Naturvidensk. 24 Bd., 1879, p. 222; Becher, Osterr. Polarst. Jan Mayen, 1886, III, p. 68. — Pecten imbrifer Posselt, Medd. om (Tronland, XIX, 1895, p. 66; ibid. XXIII, 1898, p. 12; Jensen, ibid. XXIX, 1905(1909), p. 332; Hagg; Arkiv for Zoologi, Bd.2, 1904, No. 2, p. 30; var. lamellosa Posselt, Medd. om Gronland, XXIII, 1898, p. 13, PL i, fig. i- Pecten imbrifer has been taken by the "Ingolf at: St. 115 - 116 - 98. - 97 - 87 - 90. 9- - 85, - 81 - 5+ - 59 - H3 S. of Jan Mayen 86 fm. - - - 371 W. of Iceland 138 S.W. - — . . . . s. - - .... E. - - .... N. of the Fteroes. 86 fm. 0.1° C. I valve. 371 - -0.4° - 3 spec, and a number of valves 138 - 5-9° - ca.35 spec. 450 - 5-5° - I spec, and 3 valves. no - I valve. 568 - 44° - 3 valves (fragments). 295 - 5.8° - I valve. 170 - 7 valves. 485 - 6.1° - ca. 65 spec. 691 - 3-9° - 2 valves. 310 - -0,1° - 3 - 388 - -0.4° - I spec. West Greenland. During my cruise with the "Tjalfe" I took P. imbrifer in Davis Strait at: 66°22'N.L., 57°i6'W.Iv 360 fm. 6 spec. The Swedish Expedition of 1871 found it in Umanak Fjord at 397 fin. and in Baffins Bay at 227 fm. East Greenland. Danish Expeditious have taken P. imbrifer at the following places: Off Scoresby Sound 167 fm. i valve. Forsblads Fjord 50 " ^ — 50-90 ca. 125 spec. The Ingolf-Expediiion. II. S- 25 LAMELLIBRANCHIATA. The Swedish Expedition of 1900 took P.inibrifcr at: S. E. of Pendiikim Island (74°35'N.L.) 79 fm. i spec. Jan Mayen. In addition to at the above stations of the "Ingolf", P. iiuhrifcr lias been taken by the Norwegian North-Atlantic Exped. at a depth of 263 fm. (bottoni-tenip. — 0.3" C.) and b)- the Austrian Exped. at a depth of 75 — 95 fm. Iceland. In addition to at the 8 "Ingolf" stations, P. iiuhrifcr has been taken by the "Thor" at: 63°05'N.L., 20°7'W.L 293 fm i .spec, and 10 valve.s. 62''57' - i9°58' - 500 - . I __ . 9 _ The Faeroes. As well as N. of the Faeroes, as noted above, P. iiuhrifcr has been taken (by the "Thor") S. W. of the Fseroes, at: 6i°i5' N. L., 9°35' W. L ca. 475 fm. 12 spec, and 25 valves. Remarks. The specimens to hand of Pectcn iinbrifcr from East Greenland and from Jan Mayen differ from the Atlantic specimens (W., S. W. and S. of Iceland, as well as S. W. of the Fseroes) in attaining to a greater size, namely 15 — 22 "'"'. for full-grown specimens, against 10 — 12 "'"\ in the Atlantic, as also in the fact, that the posterior ears of the shell are relatively large (cf. in PL II figs. I a, b, c, d, e and f with figs. 2 a and b). On the whole the Polar Sea form probably reaches a greater size than the Atlantic. The specimens brought home by the Dijmphna Exped. from the Kara Sea measure up to 21 """., and Leche records the maximum size from the Kara Sea as 22'""'.'); Friele and Grieg give 20'"™. as being not uncommon for high-arctic specimens, whereas the species does not become more than 11 '""'. at the Norwegian coast. Leche for his specimens found it convenient to set up a v^r. iiiajor\ I quite agree with this and propose therefore to call the southern, smaller form van minor. So far as my experience goes, the variety major also differs from the more southerh- form by having as a rule the jwsterior ears of the shell relativel\- large (comp. in PI. II figs, i a — f (xnr. major) with figs. 2 a — b (var. mii/or)). I am of opinion, therefore, that the forms major and minor represent geographical subspecies, connected respectively with the "cold" (or transitional belt to this) and the "warm" area in the deeper regions. 2) Within each of these subspecies there are numerous modifications in regard to the sculpture of the left valve. Posselt (I.e.) has some pertinent remarks on this point. Whilst Posselt received his impressions from "a consideration of the figures cited", I have been able to observe the transitions on the material before me and I may take the opportunity of illustrating these not uninteresting conditions by some figures. ') In the Vega-Exped. Veteusk. lakttagelser III, 1S83, p. 452 Leche records the .species from the Bering Sea witli an even greater size, namely 30 mi"., but the specimens in question T have had the opportunity of seeing in the Riks-Museum at Stockhohn, do not belong to this species. 2) The .specimens from St. 59 and St. 143 of the Ingolf, with negative temperatures, are small but seem, to judge fom the relatively large, posterior ears of the shell, to be the young of var. major. I.AMi:i.l.II',KAN\IlI ATA. 27 The lines of growth on the risjht valve appear as nnnierous, low and sliarp folds, whilst the left valve, in addition to similar folds, bears in general radially arranged, pored, small vesicles (PI. II, figs, ig — h), the number of which increases towards the peripliery, new ones arising regularly in the interspaces. Closer consideration shows, that the vesicles have the lower edge free and that they are .simply outgrowths of the concentric lamellre. Thus, we may find some specimens, in which the left valve in regard to sculpture only differs in the main from the right by some few, distant rows of very small, pocket-like outgrowths (PL II, fig. la), but generally their number is large (fig. ib). Other specimens have larger and fewer, rather \aulted outgrowths (fig. ic). In others again the vesicles are so broad and flat, that they almost meet one another (fig. le). Lastly, we find in the variet}' lamellosa Posselt (fig. if) a form where the vesicles are fused together to concentric, porous wrinkles, formed of projecting, down-turned lamelUe, which at their lower free margin reach to and rest on the next wrinkle; the lamellse are in general interrupted and broken, so that only remnants of them remain as sharp combs. The vesicular outgrowths are also broken off more or less and their position is then shown as a concavity in the line of growth; sometimes almost all the vesicles are rubbed off, so that the lines of growth appear like the cogs on a cog-wheel (fig. id &. li). Among other variations it may further be mentioned, that the upper part of the shell may be almost completely smooth and the outgrowths appear only towards the margin, as shown in fig. 2a; lastly, fig. 2b represents a specimen in which the left valve is almost quite smooth. I would not have entered so much into detail on these points had not Prof. A. E. Verrill and Miss Katherine Bush raised these variations to the rank of si^ecies; their I'cctcn piistulosus and P.subiDthrifcr are in fact based on specimens such as are represented in my figures ic and id. Distribution, The form major is an arctic, deep-water form (30— 40ofm., perhaps even deeper, 650 fm. M, occurring at East Greenland, Jan Mayen and Spitzbergen, in the Barents Sea and the Kara Sea^). The form minor is an Atlantic, deep-water form, which occurs in Davis Strait and off the east coast of the United States of North America, down to ca. 4o°N. L., along West and vSoutli Iceland, S. of the F"seroes and at the western and northern coasts of Norway. The "Thor" has taken it S. E. of the Fseroes (6i"25'N.L., 4°39'W.L., 210 fm.) and in the North Sea (58°32' N.L., 4°i8'E.L., 147 fm.). How far the species goes southwards along the west coast of Europe cannot be stateds), as P.imbrifcr is said not to be identical — as assumed earlier — with the Mediterranean-Atlantic P. Hoskynsi Forb.4). Pecten vitreus Chemnitz. Pallium vilreuin Chemnitz, Conch. Cab. VII, 1784, p. 335, PL 67, Fig. 637a. — Pccfcn vitreus G. O. Sar.s, Moll. Reg. Arct. Norv., 1878, p. 21, PL 2, fig. 5; Jeffrey.s, Proc. Zool. Soc. 1879, p. 561 ; Smith, ChalL Rep. XIII, 1885, p. 303. — Palliolum vilrcum Verrill, Tran.s. Conn. Acad. X, ■) St. 192 of the Norvveg. North-Atlantic Exped. lies at 69^46' N.L., i6°i5'E. L., with a depth of 649 fm. and bottom- temp, of — 0.7° C, but I have not seen specimens from here. 2j Leche's record of its occurrence in the Bering Sea is due to an erroneous determination, as shown on p. 26 note i. j) Dautzenberg & Fischer record it right down at the Azores (Dragages effectues par I'Hirondelle et par la Princesse Ahce; Mem. Soc. Zool. France 1897, T. 10, p. 192). 4) Cf. Dall, Bull Mus. Comp. Zoologj-, XII, 1SS6, pp.214 and 220. 4* 28 LAMELLIBRANCHIATA. 1899, p. 66, PI. 18, figs. 6 — 13. — Pccten ahyssorum (Loven M. vS.) G. O. vSars, Moll. Reg. ArcL Norv., 1878, p. 22, PI. 2, fig. 6. — C/ilaiiiys CV/ff/^v/ Dautzenberg & Fischer, Mem. Soc. Zool. France X, 1897, p. 190, PI. 5, figs. 5—8. Pectcn vitrcus Posselt, Medd. 0111 Gronland, XXIII, 1898, p. 11. St. 28 - 25, - 98. - 90. - 10. - 9' - 8. - 80. - 78 - 73 - 69. - 68. - 39 - 67 - 40. - !■ This species has been taken b}- the "Ingolf Expedition at: Davis Strait 420 fm. - 582 - W. of Iceland 138 - 568 - - 788 - - 295 - S. W. of Iceland 136 - - 935 - - 799 - — 486 - S. of Iceland 589 - - 843 - 865 - — 975 - - 845 - — 600 - 46. W. of the Faeroes 720 - 3-5° C. 3 spec. 3-3° - 3 — and I valve. 5-9° - I — - 4 valves. 44° - 3 valves. 3-5° - 7 spec, and 1 valve. 5.8° - 2 — - I — 6 ° - 3 valves. 4 ° - 1 valve. 4-5° - 2 spec, and 32 valves 5-5° - 2 — 3-9° - I — and 6 valves. 34° - 3 — 2.9° - 7 - 3 ° - 6 — and 3 valves. 3-3° - 16 - 4-5° - I — 2.4° - I — ) measnres: length 25 """., height 25.5 " breadth 8"'"'.; the second largest (from St. 40): length 19"""., height 19.5"""., breadth 7"'"'. Further, P.vitrcus has been taken by the "Thor" at the following places: Iceland. 63=05' N.L., 20°7'W.L 293 fra. i .spec, and 5 valves. 63°i2.5' — 20°o6' — 268 - 7 _ - I valve. ^2°57' — i9°58' — 500 - I _ - 40 valves. 62°io.5' - 19^36' — ca. 1000 - 3 _ 63^21' — i6°22' — 263—295 - 3 — Faeroes. 6i°8' N.L., 9°46'W.Iv 450 fm. i spec, (on .spine of Cidaris). 6i°i5' — 9°35' — ca.475 - 6 — and 17 valves. Remarks. Examination of the nnmerous specimens at hand has led me to the same view as that held by Jeffreys, Norman, Verrill, Friele and Grieg, namely that P.abyssorum (I^oven) 1. K- J.AMKJUUBRANCHIATA. 29 Sais is only a variety of P.viireits Cheniii. ') Uii the one hand, there are all transitions from the densely scaled to the perfectly smooth specimens; on the other, we find specimens which have just as thin valves and just as small ears as P. abyssoruvi in combination with a sculpture such as we find in /'. vitrcus. Distribution. The investigations of the "Ingolf" show that Pcctcii vifrnis does not enter into the "cold" area, but keeps to places with positive bottom-temperature (2.4"— 6° C.) in the southern jjart of the Davis and Denmark Straits, also south round Iceland over to the Faeroes, in 136 to 975 fm. 2) On the European side the species ranges from Lofoten along the Norwegian coast, 50 — 650 fm. (Sars), into the northern part of the North Sea, ca. i5ofm. ("Thor") and down into the Skager Rak, ca. 240— 350 fm. i"Thor"). Further, it occurs between the Faeroes and Hebrides, 229— 650 fm. ("Lightning"), off the west coast of Ireland, France and the Pyrenean Peninsula, 90 — 994fm. ("Porcupine"), in the Bay of Biscay, ca. 340 — 895 fm. ("Caudan"), N. of the Azores, 2240 fm. ("Travailleur-Talisman"), at the Azores, ca. 445 — 840 fm. ("Princesse Alice") 3), at the Canaries and W. of Morocco and Soudan, ca. 85— iioo fm. ("Travailleur-Talisman"), Sargasso Sea, 1650 fm. (id.) as also in the Mediterranean (to Sicily). In the Western Atlantic it occurs off Nova vScotia and Newfoundland, 57— 4oofm. and further .south as far as Florida, going down to a depth of 1537 fm. off Chesapeake Bay (Verrill). It has also been taken off the west coast of Patagonia, 140 — 400 fm., at the Philippines, 100 — 700 fm. and at the south of Japan, 345 fm. ("Challenger"). Pecten similis Laskey. Pecten similis Laskey, Mem. Wern. Soc. I, iSii, p. 387, pi. 8, fig. 8; Jeffreys, Brit. Couchol. II, 1863, p. 71, PI. 23, fig. 5. At Iceland the "Ingolf" has taken this species at: St. 98. W. of Iceland 138 fm. 5.9° C. 8 valves . 86. - - — (Brede Bugt) 76 - 6 — - 87. - - — — no - I — - 85. S.W. - — 170 - I .spec, and 15 valves. - 6. S.E. - - 90 - 7-o° C. 3 - The largest of these specimens (vSt. 98) measure: length 7™"', height 6.25""". Further, P. similis has been taken S. of Iceland at 63' 15' N. L., 22^" 23' W. L. 170— 114 fm. Numerous spec, as well as at the following places at the Faeroes: Klaksvig 10-15 fm. 2 valves. Fnndingsfjord 12— ca. 20 - coarse sand 23 — Vestmanhavn 5—6 - fine black sand 2 — 6r 40' N. L., 7° 40' W. L. 135 - 5 - 1) In his great work on the MoUusca from the "Exped. scient. tUi Travailleur et du Talisman" (T. II, 1898, p. 398) .\. Locard maintains the opposite view. 2) Posselt records a specimen from Sukkertoppen (almost in the same latitude as St. 28 of the "Ingolf) at 15 — 20 fm., but the specimen has certainly not been living at this shallow depth. 3) It can be seen from the figures, that Chlamys Chaperi Dautzenberg and Fischer (1. c.| is identical with the present species. 3° LAM ELL I B RAN C H I ATA . 13 miles S. of Myggensesliolm ca. 70 fiii. 85 valves. 9 - E. S. E. of Bispen - 70 - ca. 100 valves. 6 - N. by W. of Kalso 60 - i spec. 16 - E. by S. of south point of Nolso 80 - i valve. 13 - W. by S. of Munken - 150 - 24 — This pretty little Pecten was not known earlier from Iceland or from the Fteroes. Distribution. Pcctni siuiilis ranges from the Gulf of Aegina through the Mediterranean, from Madeira along Europe to West Finmarken and into the eastern Kattegat; over the Fteroes it reaches to South and South-West Iceland. According to Jeffreys it is also said to occur at Jamaica and Korea. The same author gives its vertical distribution at from 2 to 300 fm. Pecten groenlandicus Sowerby. Pcctni vitrciis (non Chemnitz) Gray, Parry's first voyage, 1820, Suppl. to App. p. 245. — Pi-ctcii groot- laiidiciis Sowerby, The.s. Conch. II, 1842, p. 57, PL 13, fig. 40; Sars, Moll. Reg. Arct. Norv. 1S78, p. 23, PI. 2, fig. 4. — Caiiiptoncclcs grociilandica Verrill, Proc. Unit. Stat. Nat. Mus., XX, 1898, p. 837, PI. 85, fig. 7. Pectcii grunlaiidicns Morch, Rink's Gronland, 1857, p. 94; Medd. Naturh. F'oren. 1868, p. 226; Arctic Manual, 187s, p. 133; Rink's Dan. Greenland, 1877, p.442; Friele, Nyt Mag. f. Natnrvidensk., 24 Bd., 1879, p. 222; Becher, Osterr. Polarst. Jan Mayen, III, 1886, p. 69; Posselt, Medd. om Gronland, XIX, 1895, p. 65; ibid. XXIII, i8g8, p. 9; Hagg, Ark. f. Zoologi, 1904, Bd. 2, No. 2, p. 28; Jensen, Medd. om Gronland XXIX, 1905 (1909), p. 331. The "Ingolf has taken this species at: St. 24. Davis Strait iigg fm. 2.4° C. 2 valves. - 115. S. of Jan Mayen. ... 86 - 0.1° - Numerous spec. - 116. — - - .... 371 - — 0.4° - I valve. - 126. N. of Iceland 293 - — 0.5° - 3 — - 128. — - 194 - 0.6° - 17 — - 127. - - 44 - 5-6° - 3 - - 85. vS.W. of - 170 - 20 — - iS. - - - 1135 - 3° . I _ - 81. - - - 485 - 6.1° - 4 spec. - 69. S. - - 589 - 3.9° - 6 valves. - 40. - - - 845 - 3.3° -• I - 4- E. - - 237 - 2.5° - 2 — ■ 5°- " ■ - 211 - 0.8° - 3 .sjDec. and a number of valves. " 59- ■ - - 310 - —0.1° - I .spec. LAMKLLIBRANCHIATA. 31 West Greenland. At llic uortheni part Pcclcii grocnlaiuiicus has been lakou b}- Swedish Hxpeditioiis in Unianak Fjord and in Raffins Bay, 12 — 227 f'"-) by the Fox Exped. in Melville Bay and at Cape York. On the American side it is known right np to 8i°4i' N. I^. (Discovery Bay). East Greenland. Here P. grocnlandicus has been taken both by Danisli and by Swedish Expeditions at the following- places: Off Angmagsalik 25—40 fm. clay. 15 spec. Tasiusak 30—50 - 9 ~ Odesund 5 — 15 - stones with algas. 2 — Cape Dalton 9-11 - clay with small stones. i fragment. Off Henry Land ca. 20 - stones. i valve. Turner Sound ca. 3 - i spec, and i valve. Hekla Havn 3— ^i - ca. 20 spec. Hurry Inlet 10 - clay. - 50 — Fleming Inlet 118 - red clay. i valve. ;\Iouth of Forsblads Fjord . 14 — 3 - ca. 70 spec. Forsblads Fjord 90—50 - clay with sharp stones. 6 spec. Cape Borlase Warren .... 10 - Lamiuaria. i — Sabine Island. — 4 — S. E. of Hvalros Island . . . 42—53 - nuid and stones. Numerous spec. S. E. of Pendulum Island . . 79 - - . . 2 spec. It has thus been found at many places over the distance from 65°35'N.L. to 74°35'N.L. and reaches the considerable size of 28.5"'"'. (Forsblads Fjord). Jan Mayan. According to Friele P. grocnlandicus is common at a depth of 30— loofm.; the Danish Exped- ition of 1900 took over 300 living specimens at a depth of 55 fm. and on ooze bottom, and the "Ingolf", as mentioned, found numerous specimens at a depth of 86 fm. on muddv bottom; the Austrian Exped. also dredged up numerous specimens. It reaches a length of 22 """. Iceland. In addition to the "Ingolf" stations mentioned, P. grocnlandicus has been taken at the following places by Danish Expeditions: 5 miles E. of Seydisfjordr (east coast) 135 fm. 6—7 miles N. of Borgarfjordr (N. W. coast) 85 - N. E. of Langanes (N. W. coast) 70 - I spec. I fragm. (on tube of Oniip/iis). ,^ LAMELUBRANCHIATA. 3^ Also oil the S. coast of Iceland at: 63°05' N. L., 20°7' W. L 293 fm. Numerous spec. 62°57' — i9°58' — 500 - 12 spec. & 23 valves. Faeroes. P. grociilandicns has been taken off the islands at: 63°i5' N. L., 9"35' W.L 270 fm. 2 spec. 63°03' — 9°28' — 275 - I - & 4 valve-s. 6i°i5' — 9°35' — ca. 475 - ca. 150 .spec. 6i°7' — 9°3o' — 440 - 10 spec. &: 19 valves. Distribution. Pccten groenlandicits occurs further at Spitzbergen (30-26ofm., Norweg. North- Atlantic Exped. and others), Finmarken (30 — 150 fm., Sars), in the Barents Sea (7— 250 fm., "Will. Barents") and the Kara Sea (5—125 fm., "Dijmphna", Leche) as also in the Siberia Sea as far as to ii6°E.Iy. (15— 36fm., "Vega"). It has not been met with in the Bering Sea, and it is therefore doubt- fully circumpolar. On the other hand, it occurs in the arctic seas N. of America, in the western part of Davis Strait, as well as off Newfoundland {130— 224 fm., Verrill). In high-northern seas it is one of the most frequent Molluscs and occurs in such incredible numbers, that the trawl can take it sometimes by hundredweights (cf. Krause, Mollu.sken von Ostspitzbergen, Zool. Jahrb. Abth. f. vSyst. 6. Bd., P341). Apart from its arctic distribution P. groenlandiais has also another, in the Atlantic. As shown above, it has been taken in the Atlantic S. of Iceland and S. of the Fseroes; Jeffreys records it from the waters N. of the Hebrides (542 fm.), W. and S. of Ireland (257— 517 fm., "Lightning" and "Porcu- pine"); the "Thor" has taken it off the Channel (625- 670 fm.), the "Caudan" in the Bay of Biscay (500 and 740 fm.), the "Travailleur" and "Talisman" also in the Bay of Biscay (365—610 fm.) and N. of vSpain (570—625 fm.), the "Josephine" between the Azores and Gibraltar (550 fm.), the "Travailleur" and "Talisman" W. of Morocco and W. of Soudan (410 — 05 fm.). Remarks. In high-northern regions P.grooilandicus reaches a considerable size; at E. Green- land, we have heard, it becomes up to 28.5 ""^. long, at Jan Mayen 22 "'"'., in the Kara Sea 28 "'"'. '), at Spitzbergen even 32.5'""'. 2). In comparison with these sizes all my specimens from the true Atlantic are very small; the largest is only 10.75 '""\ ^ believe therefore, that the P. grocnlandiciis living in the Atlantic is a dwarf-form. With this agrees also Locard's remark regarding the specimens taken by the "Travailleur-Talisman", that they belong to a var. minor i) and Jeffreys' statement that the specimens taken by the "Porcupine" Exped. off the British Isles were "young only"+); I believe, that the species in the warm Atlantic is already full-grown at a size, which in the Polar Sea would still be considered young. As it is still constantly stated, that the left valve is considerably larger than the right, I may say J.Collin is perfectly right when he writes (I.e., p. 452): "in most .... the valves are of the same ■) Collin has introduced the term var. major for specimens from the Kara Sea; Dijmphna-Togtets Zool.-bot. Ud- bytte, 1886, p. 452. 2) N. Knipowitsch: Zool. Ergebn. d. russ. Exped. nach Spitzbergen. Moll, uud Brachiop. I, p. 79; Ann. Mus. Zool. St. P^tersbourg, T. VI, 1901. 3) Exped. scient. du Travailleur et du TaHsman; Moll. Test. II, 189S, p. 399. ■1) Proc. Zool. Soc, 1879, p. 560. LAMELLIBRANCHIATA. ^^ size, only in a few does the inaioin of the left valve extend a trifle beyond that of the right, without however bending over it" and p. 453 (under J'"'. 26.5 "'"'. 27 - 26.5 - Quite small specimens have the ears of the shell comparatively enormously large, as is shown in fig. 7f, which represents a specimen 2""'. long. Even in the full-grown the ears of the shell may be of slightly different size (cf. figs. 7a & b with figs. 7c & d), but are yet on the whole comparatively very small, by which means the species is distinguished from the nearly related I'.piidicHs Smith and P.undatus V err ill and Smith (see p. 36). P.frigidus^ as indicated in the diagnosis, is not exactly symmetrical and it obviously rests on the flattest (right) valve, as this is always "clean", whereas the left \alve is covered with Foraminifera, worm-tubes, Scalpelluin etc. LAMELLIBRANCHIATA. 35 Remarks on '•Pcctoi fragilis Jeffreys" '). As I find nnself able to clear up the obscurity which has hitherto rested over this species of Jeffreys, I take this opportunity of making; a few remarks in this regard. Picftu fragilis was founded by Jeffreys in 1876 (Ann. Mag. Nat. Hist. (4) 18, p. 424) for a species taken by the "Valorous" Expedition in the North Atlantic, between Ireland and South Green- land, at depths of 1450, 1750 and 1785 fm. At the same time Jeffreys reports, that the Norweg. North-Atlantic Exped. had taken the same species during its cruise of 1876, at 1000 — 1500 fm.; this latter information must have come through H. Friele (of Bergen), to whom the working up of the Mollusca of the Norwegian Expedition was entrusted, sending Jeffreys a specimen of this Pecten of the northern ocean, which the latter has identified as belonging to his North Atlantic species. In 1879 Jeffreys again mentions Pcctcn fragilis, in the report on the Mollusca collected by the "Lightning" and "Porcupine" Expeditions (Proc. Zool. Soc. Lond. 1879, p. 561), a specimen having been taken by the "Porcupine" in 1869 off the west coast of Ireland in 420 fm. On this occasion two figures of the shell are given (1. c. PI. 45, fig. i). In the same year Friele stated, that P. fragilis Jeffreys was common over the whole of the deep "cold area" from the Fseroe-Shetland Channel to Spitzbergen. On comparing the "fragile" Pecten found by the "Ingolf Expedition in great depths in the "cold area" with the P. fragilis Jeffr. figured in the Proc. Zool. Soc. 1879, PI. 45, fig. i to the right, it was evident to rae, that it must be the same species, and that fig. i to fhr left ou the same Plate must have arisen from the artist turning the right valve round and publishing it as left valve, as it has the auricular sinus (for the byssus) and is on the whole a copy of the right valve. I had some doubts, however, as to how far the figure to the right had really been drawn from one of the original specimens of the "Valorous" Expedition, as it is stated regarding these in Jeffreys' paper of 1876: "Fragments only"; nor could I believe, that the specimen of the "Porcupine" Exjjedition had served as basis for the figure, as it is designated "young", whilst the figure in question represents a fairly large specimen. To still further increase the confusion, it is stated in Jeffreys' diagnosis of 1876: "the lower valve has a few slight concentric ribs, but no longitudinal striae", which does not agree with my specimens from the depths of the Norwegian Sea (nor with Jeffreys' figure) and "ears equal in size", which does not agree either. I had my suspicions, therefore, that the figure in the Proceedings of the Zool. Soc. had been drawn from a specimen from the deep arctic basin, sent to Jeffreys by Friele. I therefore asked Dr. A. C. Johansen, who was at that time studying at the British Museum in London, to examine into this matter, and through the friendly assistance of Mr. E.A.Smith, the Director of the Malacol- ogical Department, Dr. Johansen was able to send me the following information. F'rom the "Valorous" Expedition there were only rather poor fragments of "Pecten fragilis I) These remarks are a translation from my earlier article, written in Danish, on Pecten frigidus (1. c). 5* ^ LAMELLIBRANCHIATA. Jeff revs" of which a couple of very small pieces show similar characteristic, concentric folds which mark the Peclcti of the Norwegian Sea, whilst others and larger pieces obviously belong to another type. The specimen from the "Porcupine" Expedition is entire, but only ca. lo "'"'. long. — Under the name of P./ragilis, further, there were found a right and a left valve from the waters of Spitzbero-en, sent by H. Friele, but the left valve was in pieces; these valves proved to be comp- letely identical with a specimen from the "Ingolf" Expedition, which I had sent Dr. Johansen for comparison. The explanation of the matter is now quite clear; Jeffreys has identified the fragments from the "Valorous" Expedition with the deep-water Pcctoi taken by the Norwegian North-Atlantic Ex- pedition a year later; the diagnosis has been based on the specimen from the deep basin of the Nor- wegian Sea, but as the left valve of this specimen was in pieces, Jeffre)'S has made use of the larger fragments from the "Valorous" Expedition ; these belong, however, to quite a different type, obviously without striation, since they reminded Dr. Johansen of P.groenlaiidicus — from this has come the passage, which has caused so much trouble to authors: "the lower valve has .... no longit- udinal striae". Later, in the paper of 1879, Jeffreys' artist has replaced the fragmentary left valve in another way, namely, by placing the right valve on its convex side, taken its contour and furnish- ing it with a sculpture, as if it was seen from the outer side. I need not refer to the manner in which other authors have sought to explain the difficulties caused in this way. It is not at all certain, therefore, that the fragile Pecten of the Norwegian Sea with concentric folds is identical with the North Atlantic P.fragilis Jeffreys from the "Valorou.s" E-xpedition; on the contrary, I feel convinced, that there are two species, nearly related yet distinct, and for the following reasons. From the Western Atlantic off the United States (37°38'4o" N. L., 73°i6'3o" W.L., 1423 fm.) Verrill and Smith have described a Pcctoi it 11 da fits, which agrees in all regards with the Pcctcii of the Norwegian Sea except that titc cars of the shell are considerably larger, for which reason it must be considered a different species from the arctic deep-water form. It is more reasonable to conclude, therefore, that the fragments of the Atlantic P.fragilis Jeffr. from the "Valorous" Expedition and the small specimen from the "Porcupine" belong to the same species as P.iiiidattis Verrill & Smith than to the species living in the deep water of the Norwegian Sea under quite different physical conditions. P'or this reason I have given the form from the Norwegian North-Atlantic and "Ingolf Expeditions a new \V3.\\\^: frigidiis. meaning, that it lives at temperatures which are constantly under 0° C. In the same year (1885) in which P. niidatiis was founded, E. A. vS m i t h described a Pecten pudicus from the Southern Ocean E. of Marion Island (46°46'S. L., 45^31' E.D., 1375 fm.), whicli likewise shows a great resemblance to mv form from the northern cold area, but has in common with P. undatus the relatively large ears and will perhaps on direct comjiarison prove to be identical with the latter. Pecten (Hyalopecten) dilcctus Verrill &. Bush from the east coast of North America, 1813 fm., will also probably prove to belong to P. inidatus as its younger developmental stage. LAMELLIBRANCHIATA. 37 If these suppositions prove to be well-fotiiuled, tlie s\ii()ii\iii\' of llic Atlantic form will then be as follows: Pecten undatus Verrill 6c vSmith'i- 1S76. Picfcii fragilis Jeffreys, Ann. May. Nat. Mist. (4) XVIII, p. 424 (partini). - Northern Atlantic (between Ireland and Greenland), 1450 — 1785 fm. 1879. /-'.yw^'/V/.s Jeffreys, Proc. Zool. Soc. Lond. p. 561 (partini) (non PI. 45, fig. i). — W. of Ireland, 420 fni. 1885. P.uitdafiis Verrill &; Smith, Trans. Conn. Acad. VI, p. 444, PI. 44, fig. 21. — Off Virginia, 1423 fm. 1885. P.pudicus E. A. vSmith, Chall. Rep., XIII, Laniellibranchiata, p. 302, PI. 21, fig. 8. — Southern Ocean E. of JMariou Island, 1375 fni. 1888. P. biscayritsis Locard, Contrib. a la faune malacologique fran9aise, XI Monogr. des esp. app. an Genre Pecten, p. 144. — Bay of Biscay, "zones profondes". 1897. Clilamys (Psaidaviussiiun) pudica Dautzenberg & Fischer, Mem. Soc. Zool. de P'rance, 10, p. 191. — Azores, 1846 fm. 1898. Pccfni Biscayoisis Locard, Plxped. scient. du Travailleur et du Talisman, Moll. Test. II, p. 400. — N. of Spain, 1353 m.; off Santander, i96oni. ; W. of Soudan, 2635 m. 1898. Hyalopccfiii dilccfiis Verrill & Bush, Proc. Unit. Stat. Nat. Mn.s., 20, p. 836, PI. 97, fi.g. 9. — Off Marthas Vineyard, 1813 fm. 1899. H.dilrctits Verrill & Bush, Trans. Conn. Acad., X, p. go. 1899. H. It II da fits Verrill & Bush, ibid., PI. 18, fig. 5. To this species I refer a fragment of a left valve, taken by the "Ingolf" at vSt. 18. Entrance to the Denmark vStrait 1135 fm. 3.0° C. Pecten maxim us Linne. Ostrca maxiiiia Linne, Sy.st. Nat. ed. 12, i, 2, 1767, p. 1144. — Pectcii ina.xiinus Jeffreys, Brit. Conchol. II, 1863, p. 73, PL 24. A fragment, ancient in appearance, of a large valve (the ventricose right valve) was obtained by nie in the dredge on Faeroe Bank (6o°55' N. L., 8°56' W. L.) at a depth of 69 fm. Distribution. The Western Mediterranean 2) and along Europe from the Canary Isles and Madeira to Scotland, Southern Norway, Skager Rak and Bohnslan. Amussium lucidum Jeffreys. PI. II, figs. 3 a — c. Plairoiiccfia htcida Jeffreys, in Wyville Thomson's Depths of the vSea, 1873, p. 464, fig. 78.') — Amusshtm lucidum Jeffreys, Ann. Alag. Nat. Hist. (4) XVIII, 1876, p.425; Jeffreys, Proc. 1) The name Pecten fragilis Jeffreys cannot be taken into consideration, as on the one hand, as shown, it embraces heterogenous forms, on the other it has been used, as Locard has shown, both by Chemnitz and by Montagu for other species. More doubtful is the question between the names undatus and pudicus, as they were brought into use in the same jear. 2) Cf. Monterosato: Revision de quelques Pecten des mers d'Europe (Jouni. de Conchyliologie, 1899, Nr. 3, p. 4). 3) Dall is of opinion, that only the figure to the left represents A. Ittctdum, whereas the figure to the right (b) is of another species, namely A. Pourt alesianum ; Bull. Mus. Comp. Zool., vol. XII, No. 6, p. 211. g LAMEIXIBRANCHIATA. Zool Soc. 1879, p. 562; Smith, Challenger Report XIII, Lamellibranchiata, 1885, p. 317, PI. 24, fig. 2; Fi.scher & Dautzenberg, Mem. Soc. Zool. de France, 10, 1897, p. 193; Locard, Exped. scient. du Travailleiir et dn Talisman, Moll. Test. II, 1898, p. 406. The .shell slightly oblong-orbicular, the anterior margin more strongly curved outwards than the posterior, which slopes fairly steeply down towards the ventral margin, compressed, the right valve flatter than the left, somewhat translucent, glistening. The valves thin, the left almost smooth or only with the margin provided with more distinct, concentric lines, the right valve on the other hand with strong, rather dense, slightly elevated, concentric striae. Beaks small, little prominent, least on the right valve. The ears well-developed, the posterior a little smaller than the anterior, with lamellse-like lines of growth; the anterior ear on the right valve with a small sinus at the base. The hinge-margin straight, cartilage-pit small, triangular. The internal surface shining, with 10—15 elevated radiating ribs, translucent on the outer side as milk-white stripes. Height 8.5 "''"'., length 9 "'"\, breadth 2.3 '"">. It has been taken by the "Ingolf Expedition at St. 10. Denmark Strait 788 fm. 3.5° C i spec, and 10 valves. The above diagnosis, which is based on the specimens of the "Ingolf" Expedition, agrees on the whole with that given by Jeffreys in Ann. Mag. Nat. Hist. (1876). A couple of small differences, I believe, can be satisfactorily explained. For example, Jeffreys gives the number of radiating ribs as 9, but the figure in Thomson's book shows 10; further, Edg. Smith found 11 on two shells pres- erved in the British Mu.seum and 14 iisually on the "Challenger" specimens. Jeffreys says nothing as to a byssal sinus in the anterior ear of the right valve, but that such is present can be seen in the figure given by Edg. S m i t h. Distribution. Amusshiin liicidu?// has a wide distribution within the northern and tropical Atlantic'): off the entrance to the Denmark Strait, 1450 fm. ("Valorous"); 49°27'N. L., I3°33'W.L., ca. 1 100 fm. ("Thor"); N. and W. of Spain, 580—1100 fm. and N. of the Azores, 2240 fm. ("Travailleur", "Talisman"); the Azores 1000 fm. and 725 — loio fm. ("Challenger", "Princesse Alice"); W. of Morocco andW. of Soudan, 500— 1385 fm. ("Travailleur", "Talisman"); off Pernambuco in Brazil, 675 fm. ("Challenger"). Limidae. Lima loscombii Sowerby. Lima /osco/;/6// Sow erhy. Genera of shells, 1820 — 24, Lima, fig. 4; Jeffreys, Brit. Conchol. II, 1863, p. 85, PL 25, fig. 4. At the Faeroes, where it has not been known earlier, the species has been taken in recent years at the following places: 16 miles E. by S. of south point of Nolso ca. 80 fm. i valve. 13 — W. by S. of Munkeu - 150 - i — 6o°55'N.L., 8°56'W.L 69- i — ■) The form from the Southern Ocean referred by Jeffreys (1. c. 1S79) to .1. hiciiiitm as a variety (stnafaj has been separ- ated by Edg. Smith (I.e., p. 316) as an independent species: A. meridionalc. LAMELLIBRANCHIATA. 39 The largest of these shells (from the last-mentioned locality) measures 17 """. Its distribution extends from Lofoten along Europe and Africa as far as the west coast of Soudan, also into the Mediterranean to the Aegean. From the Skager Rak it goes into the south- eastern Kattegat. G. O.Sars gives its vertical distribution as from 5 — 100 fni., Jeffreys from 5—205 fm. Yet it is stated, that the "Porcupine" has taken it at great depths (4, 5 and 6 hundred fm. on the line Fal- mouth-Gibraltar, in the Mediterranean even at 1456 fm.). Lima excavata Fabricius. Ostrca excavata Fabricius, in Schroter's Naturgeschichte, II, 1780, p. 117. — Excavata Fabricii Chem- nitz, Conch. Cab., VII, 1784, p. 355, PI. 68, fig. 654. — Lima excavata Jeffreys, Proc. Zool. Soc, 1879, P- 564; Sars, Moll. Reg. Arct. Nor v. 1878, p. 24, PI. 3, fig. i; Locard, Exped. scient. du Travailleur et du Talisman, Moll. Test. II, 1898, p. 409. — Radiila (Accsta) excavata Dautzenberg& Fischer, Mem. Soc. Zool. de France, X, 1897, p. 186. This beautiful species has been taken by the "Thor" at 3 places S. of Iceland, namely at: 63'^05' N. L., 20°7' W. L 293 fm. i valve and some fragments. 63°i2.5' N.L., 20°o6' W. L 268 - 4 spec, and 7 valves (height 27.5 — 87""^.), along with a quantity of Oculina. 63°2i'N. L., i6°22'W. Iv 263 — 295 - I spec, (height 56 ™™.), along with living Oculina (Lophelia) prolifera. Although these specimens attain to a very considerable size (87"""'.) they are yet far from the maximum size of the species; Sars gives the size of Norwegian specimens as "almost equal to a palm of the hand", and our Zoological Museum possesses specimens from the Trondhjems Fjord up to a size of 160 """. Distribution. Lima excavata is best known from Norway, especially from Hardanger Fjord. G. O.Sars (I.e.) ascribes to it the following distribution: West Finmarken, Lofoten and West Norway, 150— 400 fm.; to this O.Nordgaard adds the following remark: "On our coast the species is limited to the great fiord depths with their particularly constant temperature and salinity (6 — 7° C, about 35 °/oo)- As the Vest Fiord is the most northern of the principal fiords where these physical condit- ions prevail, I am inclined to think that the mention of this species from Finmark nuist be a mistake. The northern limit should be looked upon as Lofoten, until there is definite information that it is distributed still further northwards."') Loven^) records it from Bohuslan, without stating however whether living specimens were obtained. Further information regarding this species is given by Jeffreys (I.e.); the "Lightning" took it N. of the Hebrides, 189 fm. ("A hinge and a part of the valves, quite fresh and united b\' the cart- ilage. Perhaps taken by a fish on the Norwegian coast, and carried out to sea" (!), and the "Porcupine" 1) Nordgaard: Hydrogr. and biolog. investig. Norwegian Fiords, 1905, p. 175. 2) Ofvers. Kgl. Vetensk.-Akad. Forh. 3, 1846, p. 186. .Q LAMELLIBRANCHIATA. obtained it at tliree stations off the S. W. coast of Portugal, 292—718 fm. ("Fragments of old and joung specimens. Semifossil?"). Next, it is mentioned by Dantzenberg and Fischer (I.e.) from the Azores, 595 — 900 fm. and by Locard (I.e.) W. of Soudan, 335— 1380 fm.') It is found as postglacial fossil in Norway, up to a size of 160"'"'. ^l Lima gwyni Sykes. PL II, figs. 4a — c. Livia rlliptica Jeffreys, Brit. Conch., II, 1863, p. 81; V, 1869, p. 169, PI. 25, fig. 2; Proc. Zool. Soc. 1879, p. 563; Locard, Exped. scient. du Travailleur et du Talisman, Moll. Test. II, 1898, p. 418. - Lima givyni Sykes, Journ. of Malacol., X, 1903, p. 104. The "Ingolf has taken this .species at: St. 6. S. of Iceland 90 fm. i valve. - 81. S. W. of Iceland 485 - i — Further, it has been taken at Iceland at the following places : 63°i5'N.L,., 22°23'W.L, 114 — 170 fm. 11 valves. 63°i8' — 2i°3o' — 94 - I valve. Vestmannaeyjar 68 — 70 - 2 valves. 63°i772' N. L,., i7°39' W. L 87 - black sand with shells and stones. i valve. These localities all lie off the south coast. The largest shell measures 13.5 "'"'. One of the shells from Vestmannaeyjar comes near to the variety Icvittsciila. the riljs being almost lacking. At the Faeroes it has been taken at: 6i°9' N. L., 7°54' W. L 180 fm. 2 valves. The largest of these valves is 11 "'"'. high. Distribution. This species reaches from Lofoten along the west coast of Europe into the Mediterranean to the Aegean; according to Jeffreys it is also said to have been found at Newfound- land and the northern Japan; the same author gives its vertical distribution as from 6 — 400 fm. Lima givym' \\a.s not earlier been recorded from Danish waters; in reality however it has been taken in the Kattegat, namely, a specimen at Trindelen as also a specimen and a valve in the neigh- bourhood of Fladen, 131/2 — 29 fm., but an erronous determination placed it under L.siibatiricti/afa Mtg.'^) Synonymy. With regard to the designation of the species the following information may be quoted from vSykesi): "In 1863 Jeffreys described (Brit. Conch, vol.11, p. 81) a shell from the British ■) At the place cited Jeffreys ;ilso ascribes it .n distribution to Patagonia aud Japan, but in Zool. Chall. E-^p., P.irt XXXV, 1885, p. 290, K. .v. Smith refers the specimens in question to the nearly related species IJnta goliath Sow. 2) P. A. 0 yen, in Archiv f. Math, og Naturvidensk. Bd. XXX, Nr. 3, 1909, pp. 33— 37. 3) C. G. Joh. Petersen: Om de skalbjerende Molluskers Udbredningsforhold i de danske Have indenfor Skagen, 188S, p. 122, and: Det videusk. Udbytte af Kanonbaaden "Hauch's Togter, 1893, p. 66. — Only one of the shells mentioned, namely that from No 39, belongs to L. snbauriculata . ■1) E.R. Sykes: On the Name Lima elliptica. The Journ. of Malacology, vol. X, 1903, p. 104. LamellibranchiaTa. 41 Seas tinder this name [T.. cUipticaJ. ITiifortnnately the name had been used in Augnst 1861, by Whiteaves (Ann. Nat. Hist. ser. 3, vol. \'III, p. 146) for a fcssil from the "CoralHan OoHthes of Ox- ford". Under these circumstances, as I am unable to trace any other name appHcable to the recent shell, I propose to name it Lima givym\ nom. nov." Lima hyperborea Jensen. PL II, figs. 5 a — e. Lima f 1(1(1 liyperborca Jensen, Medd. om Gronland, XXIX, 1909, p. 329, figs. la-d. The shell oval or elliptical, extremely tumid, white or yellowish white with a faint lustre. The valve is thin, slightly oblique, with the anterior margin forming a slight, regular curve, the posterior margin somewhat more strongly curved outwards above, with ca. 24 — 36 fine, btit distinctly elevated, sharp radiating ribs, disappearing outwards towards the sides, two of the central ones as a rule stronger and with larger interspace than the others, thus producing a fairly well-marked furrow, lying almost medially or a little to the anterior side of a line through the middle of the valve (sometimes however only one prominent median rib); the concentric striation extremely fine; the beaks prominent; the hinge-margin relatively long, almost straight, passing into the lateral margins at an obtuse angle; the cartilage-pit triangular; the inner side glistening silvery white or of a pearly lustre. Height 15 "'"'., length 9.5"""., breadth 9 "'"\ The "Ingolf" has taken this species at: St. 116. S. of Jan Mayen 371 fm. — 0.4° C. i spec, and fragments of 2 valves. - 139. N. of the Fseroes 702 - — 0.6° - 2 spec. Whilst the specimen from St. 116 is 20"'"'. high, the largest from St. 139 is only 4.5""^. Lima kyferborca was originally described by me from East Greenland, where it was taken by the Danish Exped. of 1900 at the following places: Fleming Inlet 118 fm. clay. i spec. Forsblads Fjord ca. 50 - clay with stones. i — Forsblads Fjord 90 — 50 - clay with stones. 12 spec, and 14 valves. The largest of these specimens measures: height 16.5 "'"'., length 10™"'. Distribution. In addition to at E. Greenland Lima liypcrbnrca lives at Jan Ma^en and in the "cold area" N. of the Fseroes, at Spitzbergen and in the Kara Sea (40— 70 fm.)'), from which I haye seen specimens preserved in the Stockholm State-Museum. It also lives presumably in the Barents Sea and in the cold Norwegian Sea, where "L.snbovata Jeffr." is said to have been taken at several places, according to Friele and Grieg^), as confusion with the present species has probably occurred. The same also holds good probably with regard to the •'Lima clliptica Jeffr." taken by the Dutch >) The specimens from the Kara Sea were referred by W.Leche to Lima sulcuhis (Leach) Loven; Kongl. Sv. Vet. Akadeniiens Handl. Bd. i6, No. 2, 1878, p. 34. 2) Norw. North- Atlantic Rxped. Zool., MoUusca III, 1901, p. 7. The Ingolf-Expedition. II. 5. ° • 2 LAMELLIBRANCHIATA. Exped. in the Barents Sea (76°3i'N. L., 45°36'E. L.) at 130 fm., bottom-temperature —i' C, as Nomann') gives the maximum size to be 11 '"™. in the length and 18™"'. in height, a size never reached by Z. elliptica so far as I know, but which might well agree with the present species. Remarks. From Lima gwyiii Sykes (= L.elliptica Jeffr. (non Whiteaves)), with which the present species has some resemblance, it is distinguished by the following characters: the form of the shell is higher; the ventral margin forms a steeper curve with the lateral margins; the radiating ribs (fig. 5e) are sharp, not serrate. L. snbovata Jeffr. is also a nearly related species, but it has more numerous (50 — 60) radiating ribs and is even more tumid. Lima subauriculata Montagu. PL II, figs. 6 a— c. Pedcn suhaurindata Montagu, Test. Brit, Suppl., 1808, p. 63, PI. 29, fig. 2. — Lima subauriculata Jeffreys, Brit. Conchol. II, 1863, p. 82, PI. 25, fig. 2. Lima sulcata Mo Her, Index Moll. Groenl., 1842, p. 16. — Lima couclusa Beck, Amtl. Ber. 24 Vers. deutscher Naturf. und Aerzte in Kiel, 1847, p. 114. — Limat/ita sulculus Morch, Rink's Gronland, 1857, p. 94. — Lima (LJmafuIa) subauriculata Morch, Vidensk. Medd. Naturh. Foren. 1867, p. 98; ibid. 1868, p. 226. — Liiiiatula sulculus Morch, Arctic Manual, 1875, p. 133; Rink's Dan. Greenland, 1877, p. 442. — LJmatula subauriculata Posselt, ]\Iedd. om Gronland, XXIII, 1898, p. 17. This species has been taken by the "Ingolf" at: St. 87. W. of Iceland (Brede Bugt) no fm. 2 valves. - 86. - - — — — 76 - ca. 20 valves. The largest of these shells measure 5.5 '"™. West Greenland. Here Lima subauriculata is common, on hard bottom and at depths of 15 — 100 fm., from the southernmost part up to Upernivik (72°47' N. L.). It reaches the considerable size of 11 "'">. Iceland. At East Iceland L. subauriculata has been taken at: 64°58' N.Iy., I3°25' W. L, 40 fm. 23 spec, and 27 valves. Reydarfjordr 68 - i valve. Nordfjordr 40 - 2 valves. Seydisfjordr, mouth 38 — 14 - i valve. — — ca. 40 - , from stomachs of haddock. 7 spec, and 7 valves. At North Iceland: Axafjordr ^o fm., stones and sand. 2 valves. •) Niederlaiid. Arch. {. Zooloi,ne, Suppl.-Bd. I, iSSi— 82, No. 10, p. 4. LAMKLUBRANCHIATA. 43 At West Iceland, at the twu statioiiii in IJrede lUigt (86 and 87) mentioned above, and at Sonth Iceland: Vestmannaeyjar 49 (ni., clay with a little nuid. 4 valves. 63°2i' N. L., i7°3i' \V. L 69 - , sand. i valve. At East Iceland the species reaches the considerable size of 10""".; of the shells from the rest of Iceland none are ov'er 5.5 """. Faeroes. Here L.sicbauriculata has been taken at the following- places: Bordovig 7—10 fm., black sand, small stones, Laminaria. 2 valves. — 10 - , sand, Laminaria. i valve. Ejde 5 — 6 - , coarse black sand. g valves. Fundingsfjord 12 — ca. 20 - , coarse sand and clay. 4 — Vestmanhavu 31/2 — 5 - , fine black sand. i sj^ec. and 10 valves. — 5-6 - , — — — 3 — - 35 — — 10—30 - 3 valves. vSorvaag 14— 1672 - i valve. 13 miles S. of IMyggenassholm ca. 70 - 4 valves. 9 — E. S. E. of Bispen - 70 - 40 — 16 — E. by S. of sonth point of Nolso 80 - 4 — 13 — W. by S. of Munkeu ca. 150 - ca. 100 valves. The maximum size of the shells taken inshore is 5 "'"'., of those taken further out to sea 6 '""'. Distribution. On the European side L. subauriculata ranges from West Finmarken') to the Canary Isles, also in the Mediterranean to its eastern part; doubtfully living in the Kattegat at present. 2) On the American side it reaches from the Strait of Florida to Labrador and the southern West Greenland; it is also said to occur on the west coast of North America, according to Jeffreys. At Norway, the Fteroes, Iceland and Greenland its vertical distribtition is from 10 — 150 fm. On the other hand, Jeffreys gives its vertical distribution to extend from 10— 1785 fm. 3) and Locard also records it from great depths, down to 2200 m. 4); but as the species of the genus Li}iia are very difficult to distinguish from one another, it is conceivable that erroneous determinations have given rise to the records of these enormous depths (cf. under L.siiiiilis n. sp.). 1) According to G. O. Sars it has not been found at East Finmarken, but it is recorded from tlie Murman Coast (Herzeustein: Beitrage zur Kenntnis der Fauna der Murmankuste und des Weissen Meeres. I. Mollusca, 1SS5, p. 642J. It is stated by W. L,eche to occur at Nova Zambia and in the Kara Sea, but this comes from an erroneous determination, the specimens in question belonging to Lima hyperborca m. (cf. the latter). 2) Only a single shell namely has been found at "Fladen" (Eastern Kattegat); as the other specimens taken in the Kattegat (including one living), which were referred by C. G. Joh. Petersen to L. subauriculata (Det videusk. Udb. af "Hauch"s Togter, 18S9, p. 66), do not belong to this species, but to L.guyni Sykes {== L.elliptica Jeffreys, non Whiteaves). 3) Proc. Zool. Soc. London, 1879, p. 563. 4) Exped. scient Travailleur-Tahsman, Moll. Test., 11, 1S9S, p. 417. 6* 44 LAMELLIBRANCHIATA. Lima similis n. sp. PI. II, figs. 7 a — c. The shell oblong, nearly equilateral, tumid, silvery white. The valves thin, with ca. 34 — 38 radiating ribs, two of the middle ones stronger than the others, with an interstitial furrow, or only one prominent median rib; the concentric lines conspicuous and close set. The beaks fairly prominent, the hinge-margin almost straight, forming with the lateral margins an obtuse angle. The inside glistening silvery white. Height 7 """., length 3.75 ™". The "Ingolf has not taken this species, but the "Thor" found it S. of the Faeroes, namely at 6i°7' N. L,., 9^30' W. L 440 fm. 5 valves. 6i°i5' — 9-35' — ca. 475 - 10 — Further, the "Thor" has dredged the same species in the Bay of Biscay at 43°37' N.L., 2°o8' W. L 250— 790 fm. 8 spec, and 15 valves. This species has a great resemblance to Liwa subauriculata, iKit the umbones are less swollen, the radiating (fig. 7 c) ribs finer and more numerous and the dorsal margin forms more distinct angles with the lateral margins than in the latter (comp. figs, i and 2). Fig. I. LimasumUs. Vi^. 2. Linm subauncuiata. I imagine, that the rccords given by authors oiL.suban- ^ ^' -^ ^' riciilata from very great depths are due to mistakes in determination, L. similis being concealed under the name of L. sicbauficitlata. Lima subovata Jeffreys. PI. II, fig. 8a— c. Lima siibovafa Jeffreys, Ann. Mag. Nat. Hist. (4) XVIII, 1876, p. 427; Proc. Zool. Soc, 1879, p. 563, PI. 45, fig. 2; Smith, Challenger Report XIII, 18S5, P- 292. St. 24. - 36. - 3& - 22, - 90. - 10. - 80. - 81 - 69. This species has been taken by the "Ingolf at: Davis Strait 1199 fm. 2.4° C. — — 1435 - 1-5° - S. of Greenland 1870 - 1.3° - - - - 1845 - 1-4° - Denmark Strait 568 - 4.4° - - 788 - 3-5° - S. W. of Iceland 935 - 4 ° - - - - - 485 - 6.1= - S. of Iceland 589 - 3.9° - I spec. I spec, and fragments of 10 valves. 3 spec, and 2 valves. I spec. 15 valves. 10 — (mostly fragments). 2 I spec, and i valve, ca. 30 valves (mostly fragments). Further, the "Thor" has taken L. subovata to the south of Iceland at the following places: 63°05' N. L., 20°7' W. L 293 fm. i valve. 62°57' — i9°58' — 500 - 3 spec, and ca. 80 valves (many in fragments). LAMELLIBRANCHIATA. 45 The largest of tliese shells incasures: height 10.5"""., length 6.5"""., the second largest is 8 mm hioii. Specially characteristic of tliis species seems to me the large number of radiating ribs (fig. 8c|; under the lens they are seen to extend right to the ears of the shell; Jeffreys has counted about 50 ribs, and on m\' specimens I have counted 60 — 70 ribs. According to Jeffreys L.subovata has been taken in the Norlliern .Atlantic off the entrance to the Denmark Strait, 1450 fm.; between the Hebrides and F;eroes, 542 fm.; off the west coast of Ireland, 420 — 1443 fm.; off the Azores, 1000 fm.; in the Western Mediterranean, 1456 fm. ■) Lima ingolfiana n. sp. PI. II, figs. 9 a— d. Tlie shell oval, somewhat ol)lique, moderately convex, silvery-white. The valves tliin, with ca. 30— 40 radiating ribs, the ridges of which are as a rule finely scaled or spined; the middlemost ribs (or rib) are stronger than the others, thus giving rise to a median furrow (or two furrows); the beaks prominent; the hinge-margin fairly short, slightly sloping, forming obtuse angles with the lateral margins; cartilage-pit triangular; the internal surface glistening silvery-white. Height 5.25"""., length 3.5 """. The "Ingolf has taken this small, elegant species at Iceland at: St. 98. W. of Iceland 138 fm. 5.9" C. i valve. - 90. - - — 568 - 4.4° - 30 valves. - 78. vS. W. of — 799 - 4.5° - I spec, and 20 valves. This species is well characterized by its somewhat oblique, more or less broadly oval contour, the postero-dorsal margin forming a blunt angle not only with the hinge-margin but also with the Ijostero-median margin; as also by the rather well-marked sculpture of its finely scaled or spined radiating ribs (fig. gd). Lima jeffreysi Fischer. PI. II, figs. loa — c. Lima Jeffreysi P. Fischer, Ann. Mag. Nat. Hist. (5) VI. 1880, p. 315; Journ. Conch. XXX, 1882, p. 52; Locard, Exped. Scient. Travailleur-Tali.sman, Moll. Test. II, 1898, p. 415, PI. XV, figs. 20 — 23. The "Ingolf" has taken this species at: St. 18. Off entrance to Denmark Strait. ii35fm. 3.0'' C. i valve. - 90. S. W. of Iceland 568 - 4.4° - i — - 69. S. - - 589 - 3-9° - I - The largest of these shells (from St. 90) is 9.5 "'"'. high. i) On the other hand, unhke Jefreys, I am unable to refer to thi,s specie.s the specimens of "L. subovati^' taken by the Norwegian and the Dutch Exped. iu the Norwegian and Barents Seas, as 1 believe, that they belong to my species Lima hypcrborea (see the latter). 46 LAMELLIERANCHIATA. Ill addition L.jcffrcysi has been taken by the "Thor" at tlie following places south of Iceland: 63°05' N.Iv., 20°7' W. L 293 fm. 7 valves (mostly fragments). 52°57' i9°58' — 5°° ■ ^'^- ^° valves (many fragments). The largest of these shells is 12""". high. This species is easily recognizable by its oblique shape, its squamular radiating ribs (fig. loc) and its lack of a central furrow. The number of ribs is 20—25, and even in the middle of the shell their breadth is less than that of the intervening furrows. L.Jeffreysi was only known earlier from the Bay of Biscay, 580 fm. ("Travailleur"). This species is nearly related to L. coti/iisa E. A. vSmith') from the Azores, Sombrero Island and Pernambuco, 450 — 1000 fm.; this again is said to be identical with L.ovata Jeffreys (non Searles Wood 2) from the North Atlantic, 1450 fm. L. scfifcra Da 11 3) from Havanna, Barbadoes and North Carolina, 52—4501111., is also a nearly related species. Lima sarsii Loven. PI. II, fig.s. iia— d. lLi))ia crassa Forbes, Rep. Brit. A.ssoc. Adv. Science, 1843, p. 193. — Lim(c)a Sarsii Loven, Index Moll. Scand., 1846, p. 32; Jeffreys, Brit. Conchol. II, 1863, p. 78, PI. 25, fig. i. — Liinatiila crassa Sars, Moll. Reg. Arct. Norv. 1878, p. 26. At Iceland this species has been taken by the "Ingolf" at: St. 98. W. of Iceland 138 fm. 5.9° C. i valve. - 85. S. W. of Iceland 170 - i — The largest of these shells (St. 98) is 4'""'. Further, L. sarsii has been taken at the Faeroes at: 61° 15' N. L., 9° 35' W. Iv ca. 475 fm. i valve (height 4""".) 61° 35' - - 4° 39' - - 210 - 2 valves (max. height 3 """.) This species, which is readily recognizable from its solid, densely and coarsely scaled shell (fig. 11 d) and creiiulated cardinal margin (fig. 11 c), was not known earlier from these regions of the Atlantic. Its distribution extends from northernmost Norwa}- (Varanger Fjord) along Europe and into the Mediterranean to the Aegean Sea-i). It is not known in the Skager Rak or the seas within this. G. O. Sars estimates the vertical distribution to be from 50— 30ofni., Jeffreys from 80— 30ofm. Nevertheless the latter records it from great depths (off Ireland and on the line from Falmouth- Gibraltar, 400, 500 and 600 fm., in the JMediterranean even 1456 fm.), and lyocard records it from 2018 meters off Cape Finisterre. 1) Challenger Report, vol. XIII, 1885, Lamellibranchiata, p. 292, PI. XXIV, fig. 6. 2) Ann. Mag. Nat. Hist. (4) vol. XVIII. 1876, p. 426. 3) Bull. Mus. Comp. Zool., XII, 18S6, p. 225; Proc. U.S. Nat. Museum, XII, 1S89, p. 250, PI. XIV, fig. 10. ^) According to Locard it is said to have been found at St. Helena. LAMELLIBRANCHIATA. 47 Mytilidae. Mytilus edulis Limic. Mytilus cdtilis Linue, Syst. Nat. cd. 12, i, 2, 1767, p. 1157; Jeffreys, IJrit. Coiichol. II, 1863, p. 104, PI. 27, fig. i; Gould & Biimey, Rep. Iiiv. Mas.s. 1870, p. 183, fig.s. 483— 84. Mytilus cdiilis Fabricius, Fauna groenl. 1780, p. 417; Moller, Inde.x Moll, firocnl., 1842, p. 19; Morcli, Rink's Gronlaud, 1857, p. 94; Vidensk. Medd. Naluili. Foren. 1867, p. 97; ibid. 1868, p. 225; Arctic Manual, 1875, p. 133; Rink's Dan. Greenland, 1877, p. 442; Posselt, Medd. oni Gronland XIX, 1895, p. 66; ibid. XXIII, 1898, p. 18; Jensen, ibid. XXIX, 1909, p. 322. At West Greenland the edible mussel is common from the southernmost parts up to at least Uuiauak; further north it is said to have been taken by the "Fox" in Melville Bay. The largest specimen (from Disko Fjord) measures no™"'., and specimens of 80— 90"^"'. are not rare. Regarding the edible mussel at Greenland H. P. C. MoLler writes in a posthumous manuscript: "The ordinary length is 64 — 77™"'., the largest specimen I possess is 105"""'. long and 50"'"'. broad; it was found at Julianehaab. It occurs everywhere on the west coast of Danish Greenland in great quantities, both on the shores by the open sea and in the bays, among the stones and in craks and crevices of the rocks. It always lives at a depth corresponding with lowest ebb-tide. Gould (Rep. Inv. Mass.) states, that it keeps to places which are laid dry by the water during ebb, but in this country it keeps to the boundary of the lowest ebb, or a little below or outside this; if it went higher up, it would be enclosed by the ice from November to May. It is eaten by the Greenlanders, boiled, raw or pickled in train-oil. It is an even more common source of nourishment for the ravens, foxes, dogs and all the animals, which are forced to seek their food on the shore at ebb-tide". It may be remarked here, however, that I have often seen living mussels in Greenland on seaweed laid dry during ebb-tide, and that Dr. V. Nordmann likewise found living Mytilus in great numbers in Nordre Stromfjord, fixed among Fucus which was daily laid dry at low-water. At East Greenland the edible mussel only lives on the southernmost parts; it is not rare in the Angmagsalik district, but the limit for its distribution lies not far north of this place, namely at ca. 66° 30' N. LM- It may reach a length of 84"-™. For the details of its occurrence I may refer to m\- paper: "On the Mollusca of East Greenland" (I.e.). At Iceland it occurs in quantities round the whole island; the largest .specimen I have seen is 85 "'™. long. At the Faeroes it is found at many places and reaches a length of 93 """. The material at hand from Iceland and Greenland shows, that Mytilus edulis is just as variable in the north as in more southern regions; but without an exact knowledge of the conditions at the different localities, it will hardly repay to discuss the variation. I) It is recorded in the literature (Posselt I.e.), that the Danish East Greenland Rxped. of 1S92 took a small edible mussel in the pelagic net out in the open sea between Spilzbergen and E. Greenland (75° 37' N. L., 6° 4' W. L.). It was n mm. long, thus long past the pelagic stage, and cannot have arrived here as floating larva. I imagine, that mussels have been attached by the byssus to the sides of the ship or algae growing there ; by the rubbing of the ice against the ship the mussel has been torn off and come by chance into the net towed behind the ship. — Cf. N. Hartz' report, that on the same Exped. he obtained numerous small algae in the net, especially when the ice was dense (Medd. om Gronland, XVII, 1896, p. 3S7, note). 48 LAMELLIBRANCHIATA. Distribution. Mytilns cdulis has a wide range within the temperate, in part also the arctic zone, both in the northern and southern hemispheres. In North America it occurs from North Carolina to Labrador; next, it occurs on the western and south-eastern coasts of Greenland, at Iceland and the Fteroes; from the west coast of Nova Zembla its distribution extends along the whole coast of Europe, and also into the Mediterranean (var. galloproviiicialis Lam.) to its easternmost end; through the Kattegat, decreasing in size, it reaches into the Baltic and up into the Gulf of Bothnia (to 62°6'N. L.). In the Pacific it ranges from Bering Sea to the Sea of Okotsk, Japan and Mexico. In the southern hemisphere the "Challenger" has taken it off Rio de la Plata, at the Falkland Islands, Kerguelen and New Zealand. — It belongs to the littoral belt; I have some youug specimens, however, from greater depths, down to 50 fni. ') In high-arctic regions the dead shells of Mytilns cdulis have been fovind at many places, where in spite of the keenest search not a single living specimen could be taken. In Europe it does not live north of Nova Zembla, yet dead shells occur in large numbers on Spitzbergen (both on the shore, at the beach and in raised deposits), on King Charles Land (Svenska P'orlandet, 25 m. above the sea) and on Franz Josephs Land (3— 6m. above the sea). At East Greenland, as mentioned, it does not live N. of 66°3o'N. L., but it has been found as fcs.sil at ca. 73°N.L., namely at the mouth of vSophias Sound (25 m. above the sea) and in the innermost parts of Franz Josephs Fjord (10 m. above the sea). These discoveries of fossil (postglacial) Mytilns cdulis indicate, that the high-arctic regions mentioned must have had a somewhat warmer marine climate than now at a not very remote geological period 2). Modiola modiolus Linne. PI. Ill, figs. I a — b (young). Mytilus modiohis Linne, Syst. Nat. ed. 12, i, 2, 1767, p. 1158; Jeffreys, Brit. Conchol. II, 1863, p. n, PI. 27, fig. 2; (Modiola) Gould & Binney, Rep. In v. Mass. 1870, p. 186, fig. 485. — Mytilus uinhilicatus Pennant, Brit. Zool., IV, 1767, p. 112. Modiola umbilicata Morch, Viden.sk. Medd. Naturli. Foi'en. 1867, p. 96; ibid. 1868, p. 224. The "Ingolf" has taken this species at: St. 87. W. of Iceland (Brede Bugt) iiofm. i .spec, (empty). [Greenland]. The species is recorded from here by G. O.Sarss) and by Dr. A. Krause^). I have no hes- itation in refusing to admit the correctness of these records; a bivalve of such a size and so easy to get could not have escaped the attention of these, whose collections are preserved in the Copen- ') N. Kn ipowi tsch (Verhandl. Kais. Russ. Mineral. Gesellscli. Bd, 43, 1906, p 271) mentions a few cases where he has found Hving, full-grown Myt. edu/i's in great depths and at a constanth- very low temperature but at the same time ex- presses agreement with a view 1 had put forward elsewhere (K. D. Vidensk. Selsk. Forhandl. 1904, p. 394), namely, that such is not the normal habitat of the .species; the specimens in (piestion must be considered to have been carried out into the deep, cold layers with seaweed, perhaps also with ice-floes (in the Kara Sea, for example, M. n/u/i's has been found on drift- ice; of. Jensen 1. c). =) For further details see Ad. S.Jensen and Poul Harder: Post-Glacial changes of climate in Arctic regions as revealed by investigations on marine deposits (Postglaziale Klimaveranderungeu. Stockholm, 1910, p. 399). 3) Sars: Moll. Reg. Arct. Norv., 1S78, p. 387. 4) Krause, in Griinland-Expedition der Gesellsch. f. F.rdkunde zu Berlin, II, i, 1897, p. 1S5. LAMELLIBRANCHIATA. 49 hagen Zoological IMuseuiii; licic there is not and never has been any specimen of ilf. iiiodiolKs from Greenland '). Iceland. Dr. A. C. Johansen mentions M. Diodioliis among the MoUnscs wliich occnrrcd in the greatest abnndance 2—3 meters below tlie liigh-water mark at the coasts of Iceland'). Fnrther, G. Bardarson has made the following observation on the northern coast: ••M.viodiolns lives here at Hunafloi at a depth of 10—15 meters and is thrown np on the beach in a heavy sea, but in small quantit}", and regarding the conditions on the west coast he writes as follows: "At Isafjordur and Breidifjordnr it is found washed up at a few places in considerable quantity. At Faxafloi it is common still more frequent at Grindavik S. of Re>kjanes, where thousands can be collected after a heavy sea. M. modiolus thus lives in shallower depths and is more frequently washed up, the fnrther south we come along the west coast of Iceland".') Lastly, the Icelandic naturalist Bj. Saemundsson writes to me, that M. modiolus is often thrown up on tlie beach in autunm on the north coast. I have made these preliminary remarks in order that the following lists may not give the impression, that M. modiolus is a rarity, for example, at East and North Iceland; its littoral occurrence and its considerable size have probably been the reasons why a comparatively small material of this species has been brought home. East Iceland: 64°58' N. L., i3°25' W. L, 40 fm. 5 spec, and r valve. Bakkafjordr 32 — 25 - 2 valve.s. The shells last-mentioned reach a length of 105 "'™. North Iceland: Husavik. washed up with Tyaminaria rhizoids. 3 spec. Skagastrand Bugt 33 fm. i — The last specimen is small, the first up to 100 """. West Iceland: 66°6' N. L., 23°59' W. L 23 fm. i spec. Dyrafjordr ca. 19 - 3 — 65°52' N. L., 23°58' W. L 33 - i valve. Arnarfjordr, beach i spec. 65°32' N.L., 24^38' W.L 22 - 4 — Grundarfjordr 9V2 - 4 valves. 64°45-8' N. L., 23°55.2' W. L 3° - 3 spec. HvalfjSrdr 24 - i — and i valve. Krossvik 8 - , shell-gravel, blue clay, stones, i — 1) G. O. Sars has also made the mistake in his "Tabulae distributionis' (op. cit.) of including Spitzbergen under its region of distribution. 2) Videusk. Medd. Naturh. Foren. Kbiivn., 1902, p. 387. 3) Vidensk. Medd. Naturh. Foren. Kbhvn., 1910, p. 62. The IngolfEspedilion. II. s- 7 CO LAMELUBRANCHIATA. Faxafjordr 25 fm. Many valves. — 1472 - I spec. — Keflavik 15 — 16 - , fine black sand. 3 fragments. Reykjavik beach, on Laminaria rhizoids 11 .spec. — 172 fill-, stony bottom. 2 spec. 8 - 4 - Hafnarfjordr beach 3 — — 4 - r - — 25 - , fine black sand and ooze. i valve. — I mile E. N. E. of Helgasker Vager ii'/j - 2 valves. It has thns been taken living even at a depth of 30 fm.; the specimen from the "Ingolf St. 87, which also lies on the west coast of Iceland at a depth of iiofm., was on the other hand empty and may possibly have been carried out with Laminaria, to the rhizoids of which M. viodioliis is accustomed to attach itself by means of its byssus. The largest specimen is 146 """. long. South Iceland: 63°3o' N. L,., 20°i4' W L 42 fm. 3 valves. Heymaey, Vestmannaeyjar beach. 4 spec. & many valves. Vestmannaeyjar 30 fm., shell-gravel. 3 valves. — 49-1 clay with a little mud. Fragments of 3 valves. The specimens washed up on the beach at Heymaey are nj? to 95 '"™. long. The Faeroes. According to earlier authors (Svabo, Landt) M. iiiodiohts occurs at many places at the Fseroes; after a heavy sea it is often found washed into the bays, not rarely hanging to large tufts of seaweed under whose rhizoids it likes to live. The largest sj^ecimens I have seen are 155"""'. long; large specimens are taken at a depth of even ca. 100 fm. In recent years it has been taken at the following places at the Frcroes: Klaksvig 11 fm., on Laminaria rhizoids. 5 spec. Fundings Fjord 12 — ca. 20 - , coarse sand and clay. i — and 16 valves. Andefjord 16 — 23 - i — Kongshavn 12 — 16 - 2 — Vestmanhavn 3V2— 5 - , fine black sand. i — — 4-) sand. I — ~ 4-5 - I - — ca. 10 - 2 — — 10 — 30 - 10 — LAMELLIBRANCHIATA. 51 Vestuiansuiid 70 fm. Sorvaag beach. — 14— 16V2 - , Thorshavn beach. — 3-4 - Nols0 beach. — deep hole at north end ca. 100 - Traiigisvaag Fjord, mouth 4—5 - , 62°29' N.L., 7°37' W.L 60 - 62°i6.5' N.L., 6°6' - 50-60 - 5 miles N. by E. of east point of Myggenses 50 - 7 — N. by E. of Myggenses Point 57 - 6 — N. by W. of Kalso 60 - i'/2 — 2 miles off mouth of Bordovig 20—30 - Bordonses in N. 57 W., i3/^ miles. . 30 - 9 miles E. of Nolso Light ca. 30 - 16 — E. by S. of south point of Nolso 80 - 6 spec. 2 — and 3 valves. ooze. I — 4 — I — 4 valves. 30 sijec. and many valves. among rhizoids of L,aminaria. i — and 3 valves. 3 — 5 — 2 — 6 — 14 — I — 15 — & many valves. 2 — I — Distribution. On the European side Modiola iiiodiolus ranges from the "warm area" of the White Sea') to the British Lsles and west of France (lyoire)^) as also through the Kattegat into the Sound and Belts; next, over the Faeroes to the coasts of Iceland. On the American side it is distrib- uted from Labrador to North Carolina, and from Bering Sea to Japan and California. Jeffreys gives the vertical distribution to be from o— loofm., which agrees with the observations from the Faeroes and Iceland (cf. above); its true habitat is the Laminaria region. Modiola phaseolina Pliilippi. Pi. Ill, figs. 2 a— b. ]\Iodiola phaseolina Philippi, Enum. j\Ioll. Siciliae, II, 1844, p. 51, PI. 15, fig. 14. — Mytilus phascolinus Jeffrey.s, Brit. Conchol. II, 1863, p. 118, PI. 27, fig. 5. Alodiola phaseolina Morch, Vidensk. Medd. Naturh. Foren., 1868, p. 224. ") According to Collin (Dijmphna-Togtets zool.-bot. Udbytte, 18S6, p. 450) a very young specimen (ig"'"'. long) is said to have been taken in the Kara Sea at 53 fm., but this case is isolated, and I doubt whether tlie species really belongs to this Sea. N. Knipowitsch also reports, that he has once obtained M. modiolus from the deep part of the White Sea, where a verj' low temperature constantly prevails (the "cold area"), but he is of opinion, that it is not the normal home of the species, but that the specimens have probably been carried out there from the coastal region with seaweed or ice-floes (Ver- handl. d. Kais. Russ. Min. Gesellsch. Bd. 43, 1906, p. 275). — The circunipolarity of M. modiolus, as maintained by some authors, is in any case a mistake; it has not been taken at Greenland (cf. antea p. 48), nor at Spitzbergen (cf. Knipo witsch, Ann. Musee zool. de I'Acad. Imp. St.-Petersbourg, VI, 1902, p. 119, note), nor on the north coast of Asia or in the waters N. of arctic .America. 2) It has been forgotten by Locard in his list: Les coquilles marines des cotes de France (1S92); in the same author's Prodrome de Malacologie Fran<^ise, MoUusques marins (1886) numerous localities are given for it (p. 491). 7* eg LAMEtUBRANCHIATA. This species has been taken by the "Ingolf at: St. 98. W. of Iceland 138 fm. 5.9° C. 15 valves. - 86. - - — (Brede Bugt) 76 - Numerous valves. - 87. - - — — no - I spec. & numerous valves. - 54. S. E. of Iceland 691 - 3.9° - i — - 55- - - - 316 - 5.9° - 3 - - 6. — - — 90 - 7° - 6 - - 51. — - — 68 - 7.32°- I — & I valve. I. N. W. of the Fseroes 132 - 7.2° - i — Previously M. phascoUna was only known in these regions from Faxafjordr in West Iceland, where lap. Steenstrup had taken 2 specimens (recorded in Jeffreys I.e.). In addition to at the above stations of the "Ingolf, M. phascoUna has in recent years been taken at many other places on the west, south and south-east coast of Iceland as well as at the Fseroes, as will be seen from the following summary. West Iceland: 66°8' N.L., 24°2i' W. L 47 fm. i spec. Faxafjordr 13 - i — — 17 ■ ) coarse shell-sand. 15 valves. — 17 — 20'/2 - , sand and shells. 3 — Skagi 21 - I valve. South Iceland: 63°i5'N.L., 22°23' W.L 170— ii4fni. 7 valve.s. 63°i8' — 2i°3o' — 94 - I valve. Vestmannaeyjar 49 - , clay with a little mud. 25 valves. — Heymaey, on beach 18 — 63°i7V3' N.L., 17°39' W.L 87 - , black sand with shells and stones. I spec. 63°2i' — i7°3i' — 69 - I valve. 63°2i' — I7°i5' — 58 - , sand, stones, shell-gravel. 9 spec, and 12 valve.s. Ingolfshofdi in N. by E. ■/, E., 9V2 miles 53 - i ~ South-East Iceland: 64^3' N. L., i5°4o' W. Iv 35 fm. 5 spec. Myre Bugt 36 - i spec, and i valve. 64^27' N. L., i3°27' W. I. 84 - 3 spec. The Fseroes: ■'y "^ 5— 6 fm., coarse black sand. 6 valves. 13 miles S. of Myggensesholm ca. 70 - 2 — 6x°56' N.L., 7°04' W.L 30 - . i spec. LAMELLIBRANCHIATA. 53 6i°4o' — 7°4o' — 135 fm. i spec, and i valve. 6i"9' — 7°54' — i8r - Temp. 8.42° C. i — 9 miles E. S. E. of Bispen ca. 70 - 3 valves. 16 — E. by S. of south point of Nolso 80 - 4 spec, and i valve. Akralejte in N. 57W., 12 miles - 150 - i — 13 miles W. by S. of Munken . 150 - ca. 100 valves. At Iceland it reaches a length of 19 """. in the shallower waters, whilst the specimen from 691 fm. (.St. 54) is only 3.5""". long and the largest specimen from 316 fm. (St. 55) 7.5""". The largest of the specimens at liand from the Fteroes is 16 "'"'. long. Remarks. The numerous specimens to hand confirm in every respect the variation remarked upon by other authors; the form of the shell is sometimes elongated, sometimes very short, but with all transitions. Modiola phascoliiia is often confused with the young of M. iiiodiolus, from which however it can be distinguished with certainty by means of the following combination of characteristics (cf. PI. Ill, ./. figs. 2a— b (M. phascoliiia) with figs. la— b (M. modiolus, young): ^^ ' The shell is more ventricose. \7 The anterior end under the umbo is less prominent. The inner edge of the antero-dorsal margin is finch' creuulated across, and the hinge-margin in from the beak is somewhat flattened and expanded and marked by minute transverse teeth. The impression of the anterior closing muscle is bounded above by a ridge-like projection from the shell-margin. The antero-dorsal margin rises more steeply and the dorsal margin is for some distance almost parallel with the ventral margin. Distribution. Modiola phascolina is distributed from northernmost Norway (Varanger Fjord) along Europe and into the Mediterranean as far as the Aegean Sea; it goes down into the Kattegat. To the west it reaches over the Faeroes to the south-eastern, southern and western coasts of Iceland. — Jeffreys gives the vertical distribution to be from o— 30Oofm., though it is not apparent where he has obtained the record of this enormous depth from; the greatest depth noted by himself lies in the Mediterranean at I4i5fm'). At Norway, according to G. O. Sars, it reaches down to 300 fm., at the Fseroes and Iceland to 691 fm., so that I am inclined to doubt the correctness of Jeffreys' record. Nor is the purely littoral occurrence quite certain, as it has not been taken living at less depths than 13 fm. at Iceland, the Fceroes, Norway or Denmark. That it may be washed uji on land is another matter; I have before me a number of apparently fresh shells, wliich had been washed up on the beach at Heymaey, Vestmannaeyjar on South Iceland (collected by Dr. A. C. Johansen). Dacrydium vitreum Mo Her. Modiola? vitrca "Holboll", Moller, Index Moll. Groenl., 1842, p. 19. — Dacrydium vitreum Torell, Spitsbergens Molluskfauna, 1859, P- ^39) P'- i) ^g- 2; Sars, Moll. Reg. Arct Norv., 1878, p. 28, PI. 3, fig. 2; Verrill, Transact Connecticut Acad., V, 1882, p. 579, PI. 44, fig- 8. ') Jeffre3S, as usual, does not mention whether the shells were "dead'' or contained the animal. 54 LAMELLIBRANCHIATA. Modiolaria vitrca Morcli, Tiling til Rink's Gronland, 1857, p. 94; Arctic Manual, 1875, p. 133; Rink's Dan. Greenland, 1877, p. 442. — Dacrydiuiii vifrcicm Friele, N>t. Mag. Naturvidensk., 1879, p. 22; Posselt, Medd. om Gronland, XIX, 1895, p. 66; idem, ibid. XXIII, 1898, p. 21; Jensen, Medd. om Gronland, XXIX, 1909, p. 325. The "Ingolf has taken this species at: St. 32. Davis Strait 318 fm. 3.9° C. 33 spec. - 28. - 420 - 3.5° - 30 — - 35- — 362 - 3-6° - 3 - - 24. — 1199 - 2.4° - 5 - - 115. S. of Jan Mayen 86 - 0.1° - 18 — and 25 valves. - 116. — 371 - — 0.4° - 2 valves (corresponding). - 117. — 1003 - — 1.0° - I spec. - loi. N. E. of Iceland 537 - --0.7° - i — - 124. N. of Iceland 495 - —0.6° - i — - 126. — 293 - — 0.5° - 12 — and 12 valves. - 128. — 194 - 0.6° - 27 - - 9 — - 87. W. of Iceland (Brede Bngt) no- 4 _ . 50 — | Quite small, I maximum - 86. — — 76 - I valve. gj^e i "'"' - 98. W. of Iceland 138 - 5.9° - 8 spec, and 25 valves. - 97- - - — 450 - 5-5° - I — - 90- - - - 568 - 4-4° - 2 - - 7 - - 85. S.W. of - 170 - 5 - - 80. — - — 935 - 4.0° - I — - I valve. - 78- — - - 799- 4-5°- 35 - -ca. 50 valves. - 58. E. - — 211- 0.8°- I valve. - 138. N. of the Faeroes 471 - —0.6° - 10 spec. The largest shell, namely of 7 """., is one from St. 58, E. of Iceland ; in the Davis Strait a size of 5 """. is attained (St. 28) and S. of Jan Mayen a size of 5""". (vSt. 115 and 116). From the stations west and south-west of Iceland the maximum size is 4 """. F~rom the two very deep stations, 24 and 117, the size is respectively only 3""". and 2.5""". There is considerable variation in regard to the form and thickness of the shell'). The spec- imens from west and south-west of Iceland (St. 87, 86, 98, 97, 90, 85, 80 and 78) differ especially from the typical D.vitrciuii in having a relatively elongated form and a less convex dorsal line; they greatly resemble the Dacrydium occidcntalc of E. A. Smith ^) (West Indies, 390 fm.), but I have not thought it right to separate these specimens as an independent species. 1) Cf. also A. Locard, who distinguishes between tlie following varieties: minor, clongata, curta, incmvata, Tcntricosa and albida; Kxped. scient. Travailleur-Talisman, Moll. Test., 11, 189S, p. 364. 2) Zool. Chall. Exp., Part XXXV, 1885, p. 282, PI. 17, fig. i. LAMELLIBRANCHIATA. 55 Elsewhere the following iiifoniiatiou may be given regardiiio; the distribution of the species. West Greenland. In addition to the "Ingolf stations in the Davis Strait, 318— 1199 fni., D.vitrcuiu has been taken at 7 localities from the southernmost (Julianehaab) to the northernmost part (72°4' N. L.) of Danish West Greenland, on clay bottom and at depths of 48—250 fin. The size is up to 5 """. East Greenland. Here D. vitrnivi has been taken by Danish Expeditions at 9 localities from Cape Dalton to Sabine Island, or from 6972°— 7472° N. L. and at depths of 10—127 fni. It reaches here a .size of 6"'™. Jan Mayen. The Norweg. North-Atlantic Exped. took D.vitrcum at 2 stations, with depths of 70—95 fm. The Danish Exped. of 1892 took 8 specimens S. of the island (70°32' N. ly., 8°io' W. L.), at a depth of 470 fm.; the Danish Exped. of 1900 took 4 .specimens and 2 valves at a depth of 55 fm., as also 3 specimens and i valve at a depth of 50— 6ofm. Lastly, as shown above, the "Ingolf Exped. found it at 2 stations at a depth of 86 and 371 fm., as also a specimen far to the south of the i.sland (St. 117) at a depth of 1003 fm., but it is only 2.5 """. long. Iceland. Apart from the stations of the "Ingolf north-east, north, west, south-west and east of the island, D.vitrcum has also been taken at the following places: 66°32'N.L., i5°i5'W.L 75 fm. i valve. 64°58' — ii°i2' — 300 - —0.38" C. I spec. The Faeroes. Besides at the "Ingolf station N. of the Faeroes (St. 138, depth 471 fm.; maximum size of the specimens 4""".) D.vitreiiin has been taken at the following places: 63^14' N.L., 9^46' W.L 260 fm. 18 spec. 63°03' — 9°28' — 275 - I valve. 5 miles N. b)- E. of east point of M)-ggences 50 - 2 valves. 6i°4o' N. L., 7°4o' W. L i35 - i ^'alve. 6i°i5' — 9"35' — ca.475 - 2 spec, and 9 valves. 6i°7' _ 9°3o' — 440 - I valve. 6 miles N. by W. of Kalso 60 2 valves. 13 — W. by S. of Munken - i55 ' 9 — From the deepest of these places (475 fm.i the specimens have a size of 3.5"""., from the other places still smaller (1—3"™.). 56 LAMELLIBRANCHIATA. Elsewhere D. vitrcum ranges from the Kara Sea and Spitzbergen to the Mediterranean and the Azores; on the American side from the Gnlf of St. Lawrence to Campeche. It is said to occur down to a depth of 2750 fm., and in arctic regions it reaches as high np as 10 fm. (cf. under East Greenland). Idas argenteus Jeffreys. PI. Ill, figs. 3a — e. Idas argenteus Jeffreys, Ann. Mag. Nat. Hist. (IV), vol. XVIII, 1876, p. 428; Proc. Zool. Soc. 1879, p. 570, PI. 45, fig. 3; Proc. Zool. Soc, 1882, p. 683. Shell having the shape of an irregular parallelogram (varying from rhomboidal to oblong), of a delicate texture, rather opaque, iridescent; it is covered with a pale brownish-yellow periostracum, which rises into fibrous excrescences on the posterior side; under the periostracum the shell is silvery white, except the beaks which are reddish brown ; sculpture, very fine and close-set transverse striae and microscopic longitudinal striae, radiating from the beaks; margins straight at the back and in front, rounded on the anterior and smaller side, and sloping from the back with a curved outline on the posterior side; beaks circular and incurved, placed near the anterior side; an internal and long cartilage covers the hinge; hinge-line nearly straight, but obtuse-angled at the hinge; hinge-plate narrow, minutely and closely denticulated on both sides of the hinge; inside polished and nacreous; edge plain; scars inconspicuous. Size of the largest specimens about 8""". In 1876 Jeffreys described the species almost as above, the additions and changes made by himself in 1882, however, being added. This small M\tilid was taken by the "Ingolf at: St. 67. S. of Iceland 975 fm. 3° C. ca. 260 spec. The specimens of the "Ingolf'-Expedition agree extremely well with the descriptions of Jeffreys. A radiating striation however can hardly be seen and the hairy periostracum is often distributed over a greater part of the shell, mostly however on the posterior and dorsal surfaces. Distribution. During the "Valorous" Cruise of 1S75 one valve was taken in the North Atlantic (56°ii'N. L., 37°4i' W.L.I at 1450 fm. The "Porcupine" Expedition of 1869 also found a shell in the Bay of Biscay at a depth of 994 fm. Lastly, it was taken on the cruise of the "Triton" between the Hebrides and the Fseroes at 516 fm., "inhabiting deserted tubes of Teredo megotara in a large water-logged piece of pine-wood, to which the Idas had fixed itself by a strong byssus". The specimens of the "Ingolf'-Exped. were taken south of Iceland (6i°3o' N. L., 22°3o' W. L.) at 975 fm., under similar conditions to the last; the trawl brought up two large pieces of pine-wood, which had been pierced through and through by Teredo; in some of the Teredo tunnels were in addition mud and worm- tubes, further worms and small bivalves, namely Idas argenteus. In 1882 Verrill mentions an "Idas argenteus Jeffreys van? lamellosus Verrill (perhaps sp. nov.)", taken by the "Fish Hawk" in 1881 at New England off Martha's Vineyard (S. S. W. V4W., i03'/j miles) at a depth of 335 fm.'). On this Jeffreys (I.e. 1882) makes the following comment: >) E..\. Verrill: Catal. of Marine MoUusca added to the Fauna of New England; Trans. Conn. Acad. vol. V, 1882 (p. 579). LAMELLIBRANCHIATA. 57 '•Idas argenfats is probably the species of that name noticed by Verrill as xar. laiiirllo.sa", and the added knowledge of l(f(7s a/or/z/r/ts o1)tained in that year really disposed of the pcctdiaritics of \' err ill's /(/tis. Modiolaria. The 4 northern species of this genus may, according to my experience, most readily be dis- tinguished from one another iu the following manner: The shell radially striated over the whole M.faba. not distinctly separated M. nigra. only on anterior or also on the posterior area. Central and poster- ior areas of shell separated by a dia- o-onal fur- Central area smooth M. discors (cum var. lavigata et subsfriata). shagreen-like wrinkled M. corrugafa. Modiolaria discors Linne. The true Modiolaria discors Linne does not occur at Greenland, Jan Mayen or Iceland. The species is represented here by "Modiolaria Icevigata Gray" and "Modiolaria suhstriata Gray", which I do not consider separate species, but varieties of a species which also embraces "Modiolaria discors Linne". The last name has the prior right by age and must consequently have the advantage in the designation of the species. var. Icrvigata G r a y. PI. in, fig.s.4a— b. Modiola Iccvigafa Gray, Parry's first voyage, Suppl. to App., 1824, p. 244. — Crenclla lavigata T o r e 1 1, Spitsbergens Mollu-skfauna, 1859, p. 133. — Modiolaria discors Gould & Binney, Rep. Invert. Mass., 1870, p. 192, fig. 489. — Modiolaria Iccvigata Sars, Moll. Reg. Arct. Norv., 1878, p. 29, PI. 3, fig. 3; Leche, Vega-Exped. Veteusk. Arb. Ill, 1883, P- 45°! P'- 34i figs. 27—28. Alytikts discors Fabricius, Fauna groenl., 1780, p. 418. — Mytilus discors^ arciicus Fabricius (partim), K. D. Vidensk. Selsk. Skr. 1788, p. 453, figs, i & 4 — 6. — Modiola discors Moller, Index Moll. Groenl., 1842, p. 19. — Modiolaria discors Beck, in Gaimard, Voyage de la Recherche, PI. 17, fig. 2a— h. — Modiolaria Icrvis Beck, ibid. PL 17, fig. 3f. — Modiola discors Beck, Amtl. Bericht 24. Versamml. deutsch. Naturf. in Kiel, 1847, P- ^^S- ~ Modiolaria Iwvigata Morch, Rink's Gronland, 1857, p. 94; Vidensk. Medd. Naturh. Foren. 1868, p. 224; Arctic Manual, 1875, p. 133; Rink's Dan. Greenland, 1877, p. 442; Bee her, Osterr. Polarst. Jan Mayen IH, 1886, p. 69; Posselt, Medd. om Gronland, XIX, 1895, p. 67; ibid. XXIII, 1898, p. 25; Jensen, ibid. XXIX, 1909, p. 326. — Modiolaria cor ruga la (non St imps on) et Icevigata Hagg, Ark. for Zoologi, Bd. 2, No. 2, 1904, p. 22 & 23. The Ingolf-Expcdition. II. j. 8 58 LAMELLIBRANCHIATA. var. S2ibstriata Gray. PI. Ill, figs. 5 a— b. Mytilus discors, arctiais Fabricius, K. D. Vidensk. Selsk. Skr. 1788, p. 453 (partim), figs. 2 & 3. — Modiolaria lavis Beck, in Gaimard, Voyage de la Recherche, PI. 17, fig.s. 3a — e. — Modiolaria^ discors Morch, Vidensk. Medd. Naturh. F'oren. 1868, p. 224. — Modiolaria lavigata var. siib- striata Posselt, Medd. om Gronland, XIX, 1895, p. 67; ibid. XXIII, 1898, p. 26; Jensen, ibid. XXIX, 1909, p. 326. — Modiolaria suhslriala H ag g. Arch, for Zoologi, Bd. 2, No. 2, 1904, p. 25. The "Ingolf" has taken this species at: St. 33. Davis Strait 35 fm- 0.8° C. i spec. 1 var. - 34. — — 55 - I ~ very young I Icrvigafa. - 119. Norwegian Sea loio - i — young (empty), \z.x.substriata. At West Greenland the species is very common from the southernmost part of the land as far northwards as the investigations extend, namely to N. W. of Cape York; on the American side it is still met with in Franklin Pierce-Bay at 79°25'N. L. It prefers shallow water, o— 3ofm., but it is said to live also in greater depths, down to 100 and 200 fm. The variety substriata is less common than lavigata. The largest specimens at mj- disposal of var. laevigata measure 46 "'"'., of var. substriata 30"'"'.; O. Fabricius mentions specimens of up to 50™"'. At East Greenland the sj^ecies has been taken at many places, sometimes in large numbers, from Angmagssalik as far north as collections have been made (Shannon Lsland at 75 — 75'/2°N. L.). The depths noted are o — 30 fm. The variety Urvigata is also by far the most abundant here; the largest siDecimen of this variety measures 36.5 """., of stibstriata 32 """. Jan Mayen. The Austrian Expedition took 13 specimens up to 28 """. long on the north side of the island, at a depth of 8 — 13 fm. The Danish Exped. of 1900 took some smaller specimens at 15 and 50 — 60 fm. At Iceland the species is probably common all round the island, from lowest water') and (in small specimens) out to 50 — 60 fm.; the localities mentioned below hardly give a correct picture of its distribution, as only few dredgings were made in very shallow water, where the species mainly lives. The variety hvvigata, which is the most frequent, reaches a length of 48 "'"'., and among the var. substriata there is one of 52 """. East Iceland: Lonsvik 8 — 10 fm., fine black sand. i spec. Berufjordr, Djupivogr 3 - , on L,aminaria rhizoids. 2 — — — 6-, mud with black sand. i — — — 8 - 2 — — — 10 - 3 — Breiddalsvik 14 - ^ — ') A. C. Johansen records Modiolaria lavigala among the Molluscs which occurred iu the greatest abundance 2—3 meters below the high water mark at the coasts of Iceland. Vidensk. Medd. Naturh. Foreu. 1902, p. 387. LAM ELLIB RANCHIATA. 59 Faskrudsfjordr, Hafiiarnes 50 — 10 fin., l)Iuc day. 2 spec. Reydarfjoidr 60—80 - i — - 70 - I - Seydisfjordr at Skalanes on I.aniinaiia ihizoids. 7 — — - — 6 - , on Ivaniinaria leaves. i — — - — 7—8 - 2 - — - Brinnics 8—4 - i — Bakkafjordr 12 — 15 - 7 — 52—20 - 15 — Finnafjordr, Gunolf.svik 12 - i — -AH these are for the nicst part quite small specimens, due to chance naturally; the largest specimen is only 25 """. long, but in the »Stockholm Museum I have seen a specimen from Berufjordr, which was 48 """. long. The variety siibsfriafa is rather frequent, comparatively speaking, in the material at hand. N o r t h I c e 1 a n d : Thistilfjordr 10 fm., sand, coral. 1 spec. KoUafjordr 7 — — 10 - I — — Hiiuafloi 5- i — Skagastrand 4 — — Bugt 2,2, - I — 66°36'N.L., 2i°57'W.L 32-37- i — Though there happens to be only such a small material from this part of the coast, it neverthe- less contains large specimens, of the variety Icrvigata up to 48 "'"'., and of the \3.x\&i\ snhsfn'ata of 52 mm West Iceland: Hofnvik 10 fm. i spec. Adalvik 6—9 - 3 — Isafjordr i — Onundarfjordr '/a — o - i — Dyrafjordr i — 65°52'N.L., 23°58'\V.L 33" i - 65°i7-5' — 23°32' - 7-12 - I — Hvalfjordr 24 - 3 — Faxe-Bugt 15 — Reykjavik 20 — All these specimens belong to the variety Icevigafa ; the largest (from Onundarfjordr) is 45 """., the second-largest (from Reykjavik) is 44.5 "■"'. long. 8* 6o LAMELIJBRANCHIATA. South Iceland: Vestmannaeyjar beach i valve. — 10—15 fm. I spec. These specimens belong to the variety sithsfriata and reach a length of 18""". [i\t the Faeroes the species has not been /oiiiid\. Remarks. At Iceland and Greenland tlie species occurs, as mentioned above, tmder two main forms : a. Modiolaria discors L. var. lavigafa Gray (PL III, figs. 4a — b): the shell somewhat compressed, posteriorly high, rounded-truncate; the posterior area without radiating stride. b. Modiolaria discors L. var. snbstriata Gray (PL III, figs. 5a — b): the shell ventricose, posteriorly low, rounded-pointed; the posterior area with radiating striae. But each of these forms again is subject to variation. The typical Icrvigata is a high form, but even among the full-grown we meet with specimens whicli are much more elongated than is usually the case. The typical Iirvigata does not have the radiating strise on the posterior area, but sometimes a faint striation may be seen here'). In the typical substriata the postero-dorsal margin slopes rapidly downwards, but we also find specimens in which the slope of the posterior margin is less abrupt. The typical siibsfriafa has the posterior area distinctly striated radially, but sometimes the striation is not to be seen, even under a lens ("Modiolaria Icrvis" Beck I.e.). The two forms frequently occur together and one is often at a loss to determine to which of the forms a given specimen has to be referred; in the case of snuil! specimens it is often quite impossible. Modiolaria Ice.-vigata-siibstriata are arctic and circumpolar forms, whose southern boundaries lie at Massachusetts, Lofoten and northern Japan. Viewed in a wider sense, including also Alodiolaria- discors, the species is distributed further along the rest of West Europe to Madeira, including the Kattegat-Baltic (to Kiel and Neustadter Bugt) and the Mediterranean 2). In opposition to G. O. Sars I must maintain, that Modiolaria substriata and Mod.lccvigata are not distinct, but forms of one and the same species. And I am most inclined to believe with Jeffrews, that Modiolaria hcvigata Gray and Modio- laria discors Linne are specificalh- identical. Against this G. O. Sars has objected very definitely and I can in so far agree with this author, that there is not an excessively great resemblance between Mod. discors and an adult, typical Mod. Icevigata ; on the other hand, I certainly consider it as more than probable, that Mod. discors is nothing else but a southerns), pygmy-t) and slightly altered form ') I exclude here the fact, that all kevigata in the very young stages have the posterior area radially striated and in the adult condition retain this striation on the umbonal region; the striation is obviously a characteristic of the 3'oung stages. =) Bucquoy, Dautzenberg and Dollfus however write in their oft-cited work, on the marine Mollusca of Roussillon, that the occurrence of Mod. discors in the Mediterranean requires to be confirmed; they mention various cases, in which Mod. 7narmornta Forb. has been confused with Mod. discors. i) Mod. discors is certainly very commonly regarded as an arctic form, but the basis for this is undoubtedly a con- fusion with the form sudsiriata; among many hundreds of specimens, which I have examined from arctic regions (Greenland, Iceland, Spitzbergeu, Kara Sea), I have not found a single one of the true discors ; this hardly goes further than northernmost Norway or Murman Coast, further east and north it is replaced by the substriata form. As mentioned by Sparre Schneider (Tromsosundets moUuskfauna ; Tromso Museums Aarshefter VIII, 18S6, p. 65) the form snbstriata ("Mod.lctvis Beck") does not occur at Norway — for the simple reason, in my opinion, that Mod. discors is its modification in boreal regions. 4) The maximum length of Mod. discors y^\. Denmark and Norway _) is 20"""., whereas Mod. substriata becomes over 50 "'m. long. LAMELLIBRANCHIATA. 6l of ••Mod.sii.bstriata" , so small is the difference between them"). Mod.discors (PI. Ill, figs. 6a — b) is on the whole a more oblong form; this is the essential difference. But whilst maintaining, that Mod. Iccvigata, Mod. substriata and Mod. discors are identical specifically, I may yet emphasize that in their typical shape they are representatives for just as many special forms and must not be summarily thrown together. Furthermore, the form discors, as I know it from Danish waters, is also not a little variable; frequently the posterior area is distinctly striated, but sometimes it appears almost smooth (cf. var. scmilcrvis Jeffreys, Brit. Conchol. II, p. 127); I have even before me at this moment a specimen from the Great Belt (Sveudborg), which combines a striation such as we find in substriata with the form of a typical Iccvigata, or on the whole shows a great resemblance to a very young Mod. IcBvigata. In conclusion I ma\' quote some little known observations regarding the biology of this species. In his paper "Om Ueens-Muslingen" (i.e. M. discors \ds. Iccvigata and substriata) O. Fabricius') writes as follows: "This Bivalve I have found to be of common occurrence in Greenland, where it is called Bibibiarsuk ; I do not know the certain origin of this word one might be inclined to think, that the Greenlauders have found this name suitable for the whistling or hissing noise, this Bivalve . . . produces when it has stood for a long time closed at ebb-tide for want of water and then with the coming of the flood begins to open again. It is attached by its fine silk (byssus) to large stones or rocks in the sea, the largest end sticking upwards, the open side turned towards the stone or foreign body, to which it is attached. It lives preferably so far from the land, that it does not become dry except at spring-tides when the greatest ebb occurs. On the blind rocks out to sea, therefore, it is most uumerous .... When its silky hairs have been broken by the waves or other cause, I have seen it stretch out its foot, attaching it to the solid rock, elongating and contracting it, and thus push itself forwards .... the fattest and largest are found on clay bottom " In a manuscript left by H. P. C. Moller we find: "It occurs everywhere in quantities on the coast of Danish West Greenland and especially where there is shallow water, partly on Laminaria, more rarelv on Fucus, partly among the string-like algal forms and among stones, down to a depth of 20 fm. or still deeper, e. g. at Nennortalik, Godhavn; I have taken it in 30 fm. opposite Nepisene at a distance of 8 Danish miles from the coast." And in a notice: "Ueber Aiytilus discors" lap. Steenstrup makes the following remarks on Modiolaria discors var. laevigata at Iceland: ". . . . Noch raehr zeichnet sich diese Muschel durch iliren selir ausstreckbaren Fuss aus, welcher ihr erlaubt, die Byssusfaden iiicht nur um die Seiten der Schalen, sondern audi iiber den Riicken derselben herumzuffihren; dadurch kann sie sich ganz mit einer Byssushiille umgeben oder sich wie in einem Byssussack verstecken. Die Enden der ausseren Bys- susfaden werden auf kleinen Steinchen, Muschelschalentriimmern und dergleichen festgeheftet, so dass der Byssussack ganz einem Steinhaufchen gleicht; die innere Wand der Byssushiille ist dagegen selir glatt, aus dichtliegenden, sich kreuzenden Byssusfaden gebildet, und schliesst sich den Muschelschalen ziemlich dicht an. Nur das hintere Ende der Hiille hat eine Oeffnung, sonst ist sie ganz geschlossen. In seichten ]\Ieeresbusen, in welchen der Boden mit grobem Sande und Grande bedeckt war, hat S. 1) Leche has obviously been of the same opinion, as he writes (I.e. p. 451), that the Mod.discors from Kiel Bay, sent him by Mobiiis, cannot be specifically distinguished from Mod. Iievfs Beck; Leche refers to this in connection with the fact, that G. O. Sars had erroneously identified Mobius' Mod.discors with Mod. corrugata Stimpson. 2) Nye Samling af det Kgl. Danske Videnskabernes Selskabs Skrifter, 3. Deel, 1 788, p. 453. ^2 LAMELLIBRANCHIATA. sehr oft bedeutende Flachen von den oben erwahnten Steinhaufchen eingenomnien gesehen; in jedeni derselben steckte eine lebende Mytiliis discors-Mxxs^^, ganz wie eine Puppe in ilirer Puppenhiille" '). Modiolaria corrugata vStimpson. PI. Ill, figs. 7 a— d. Modiola discors Gould [iion Linne), Rep. Invert. Mass. 1841, p. 130, fig. 84. — My f Hits cornigata vStimpson, Shells of New England, 1851, p. 12. — Modiolaria corrugafa Gould and Binney, Rep. Invert. Mass. 1870, p. 193, fig. 491; Sars, Moll. Reg. Arct. Norv. 1878, p. 30, PI. 19, fig. 2. Modiolaria corrugata Morch, Rink's Gronland, 1857, p. 94; Arctic J\Ianual, 1875, p. 133; Rink's Danish Greenland, 1877, p. 442; Posselt, Medd. om Gronland, XXIII, 1898, p. 23 (partini). — Alodi- olaria nigra Walker (iioii Gray), Journ. Roy. Dublin Soc, vol.3, i860, p. 70. At West Greenland this species is not common according to Posselt. In this I can confirm Posselt and I even believe, that it is more rare than he thought, as he has in several cases confused Modiolaria nigra with the present species. Specimens which are certainly M. corrugata I have seen in the Copenhagen and Stockholm Zoological Museums from the following West Green- land localities: Plskeuses, 70 fm., shell bottom; Godthaab, 50— 6ofm.; Disco, Harungen, 160 fm., clay bottom; Godhavn, 70 fm., clay bottom; Umanak, 12 fm. and 25 — 35fm., stony bottom; N. W. of Cape York, 5— i2fm., sand mixed with clay. From each locality there is only one or a couple of specimens. According to Jeffreys'), the so-called "Modiolaria nigra" taken by the "Fox" at Cape York and Port Kennedy belong to this species. — The largest Greenland .specimen which I have seen is 15.75 "'"'• long. [At East Greenland M. corrugafa is stated to have been taken by the Swedish Exped. of 1900, according to R. Haggj); I have had the opportunity of seeing the specimens in question and found, that they were in reality the two varieties Icrvigata Gray and substriata Gray of Modiolaria discors L,. M. corrugata has thus not yet been found on the east coast of Greenland]. [On the north side of Jan Mayen the Austrian Polar Station is said to have taken 2 specimens, according to Becher^), but we do not know, whether the determination was correct]. [That Mod. corrugata occurs at Iceland, as stated by VerkriizenS), I consider as more than doubtful; the species is not represented in the systematic collections made from the Danish side. I imagine, that the specimens Verkriizen obtained at Reykjavik by dredging in July 1872, were M. discors var. substriata]. Distribution. In addition, we have more or less certain records that Modiolaria corrugata lives at Spitzbergen, ca. 372— 63 fm. (Torell, Knipowitsch) and at Finmarken, 20 — 50 fm. (Sars), in the Kara Sea, 20 — 78 fm. (Collin), in the Polar Sea of Siberia, 9—12 fm. (Lechei, in the Bering Sea, i5-2ofm. (Krause) and on the north-east coast of America down to Cape Hatteras (Dall). ') Amtl. Bericht uber die 24. Versamml. Deutscher Naturf. uud Aerzte in Kiel, 1S47, p. 222. 2) vScient. Proceed. Roy. Dublin Soc, N. S., II, 1S80, p. 12S. 3) R. Hagg, Arkiv for Zoologi, Bd. 2, No. 2, 1904, p. 22. 4) Becher, Osterr. Polarst. Jan Mayeu, III, 1SS6, p. 69. 5) T. A. Verkruzen: Dredging-Excursion to Iceland. Ann. Mag. Nat Hist. 4 ser. Vol. X, 1S72. p. 372. LAMELLIBRANCHIATA. 63 Remarks. Great uncertainty prc\ails among authors regarding Modiolaria corrugata ; often it is called a "transitional form" to other arctic species of Modiolaria^ and especially to M. discors L. var. subslriofa Gray ("M. Icrvi's Beck"). From a close investigation I have come to the result, that M. corrugata is an exceedingly well defined species. M. corrugata certainly shows some resemblance in habit to M. discors var. substriata., but is readily distinguished from this by the middle area being not smooth or simply striated (cf. PI. Ill, fig. 5 c) but showing under the lens a shagreen-hke wrinkling of the surface, as shown in fig. jd on PI. Ill (cf. also Krause: Bin Beitrag zur Kenntniss der MoUusken- Fauna des Beringsnieeres, p. 19) '). A similar kind of surface is also found, however, in M. nigra; but in the latter the posterior, striated area grades evenly over into the middle area, whereas in M. corru- gata the middle area appears depressed along the boundary line towards the posterior area, as in M. discors; further, in M. corrugata the radial striation is coarser, the shell more ventricose (cf. measure- ments of M. corrugata with those of M.nigra) and with more prominent umbones. In regard to shape, moreover, M. corrugata is rather variable, as will be seen from the following measurements of a number of specimens: Length of Height of Height Breadth of Breadth ^'^^ ' ^ sheU shell Length shell Length Greenland 15.75 """• 1° "'". 63.5 % 7-5 ""■• 47-6 % — 14-5 - 9-5 - 65.5 - 7-5 - 517 - — 14-25 - 9 - 63.2 - 7.5 - 52-6 - — 12.3 - 7-75- 63 - 7 - 56-9 - — 8 - 5.75 - 71-9 - 4-75 - 59-4 - Spitzbergen 26.5 - 17 - 64.2 - n - 4i-5 " — 24 - 15-75 - 65.6 - 10.25 - 42-7 - — 22.5 - 14.75 - 65.6 - 10 - 44.4 - — 18.75 - 12 - 64 - 8 - 42.7 - — 1375 - 8.75 - 63.6 - 5.75 - 41-8 - — 13.25 - 8.8 - 66.4 - 5.75 - 43-4 - — 13 - 8.75- 67.3 - 5.5 - 42-3 - 8.5 - 6 - 70.6 - 4.75 - 55-9 - — 8.25 - 5-75 - 69.7 - 4 - 48-5 - Kara Sea 21.5 - 13 - 60.5 - 9 - 4i-9 " Modiolaria nigra Gray. Modiola nigra Gray, Parry's first voyage, Suppl. to App., 1824, p. 244. — Crcvclla nigra Torell, Spitsbergens Molluskfauna, 1859, p. 130. — Modiolaria nigra Jeffreys, Brit Conchol. II, 1863, p. 128, PI. 28, fig. 4; Gould & Bin ney. Rep. Invert. Mass. 1870, p. 190, fig. 487 (jnv.) &488. Modiola discrcpans Moller, Ind. Moll. Groenlandise, 1842, p. 19. — Modiolaria striatula Beck, in Gai- mard. Voyage de la Recherche, PI. 17, figs, i a— f ; Amtl. Bericht 24. Versamml. dentsch. Naturf. I) Archiv fiir Xaturgeschichte, 1885. 64 LAMELLIBRANCH lATA. in Kiel, 1847, p. 115. — Modiolaria nigra Morch, Rink's Gronland, 1857, p. 93; Vidensk. Medd. Naturh. Foren. 1867, p. 96; ibid. 1868, p. 224; Arctic Manual, 1875, P- 132; Rink's Dan. Greenland, 1877, p. 442; Posselt, Medd. om Gronland, XXIII, 1898, p. 27; Hagg, Ark. for Zool., Bd. 2, No. 2, 1904, p. 26; Jensen, Medd. om Gronland, XXIX, 1909, p. 328. West Greenland. The species has been taken at many places from the sonthernmost part up to Proven (72° 23'N. L.), and it will certainly prove to occur even further north, as it has been taken on the American side right up to 78°45' N.L. '). The depths recorded lie between 10 — 200 fm. It attains to a very considerable size, up to 62 "'"'. Regarding this species H. P. C. Mo Her writes in a manuscript preserved in the Museum here: "This bivalve is living along the whole coast of Danish West Greenland, but only solitary and where the sea is deep (30— 6ofm.) and the bottom is clay. Young individuals are frequently to be met with; the adults on the other hand are rather seldom to be found, because they conceal themselves digging down deep in the clay." East Greenland. M. nigra has been taken at 6 localities between Angmagssalik (65°35' N. L.) and Cape Borla.se Warren (74°2o' N. L.), at depths of ca. 3 — 19 fm. The largest specimen is 45.5"'"'. long. Iceland. M. nigra has been taken all round the island, at depths of ca. 6 — 50 fm. The largest specimen is not less than 67 ™"'. long, but as a general rule only small specimens are taken. The various localities are shown in the following lists. East Iceland: Berufjordr, Djupivogr 6 fm., mud with black sand. 45 spec. Faskrudsfjordr 50 — 20 - , blue clay. 2 — Reydarfjordr 44- i — Seydisfjordr at Skalanes 8 — 7 - 10 — Bakkafjordr ca. 10 - 2 — — 12 — 15 - , black sand. i — — 52 — 43 - Fragments of a large specimen. Finnafjordr 18 - 3 spec. The specimen from Rejdarfjordr is 67 """. long, the specimen from the greatest depth in Bakkafjordr has also been of considerable size, but the others are quite small specimens. North Iceland: Thorshofn 6 fm. i valve. Axafjordr 22 - i — Ofjord at Svalbardseyri 10 — 20 - 4 spec. These are small specimens. ') Grieg: Rep. .Sec. Norvv. Arctic Exped. in the "Fram"', No. 20, 1909, p. 9. LAMELLIBRANCHTATA. 65 West Iceland: Rilni Huk-Straumnses 30 fin., in liaddock. 2 spec. Dyrafjordr, inside Thingnaes 10— la'/z - , 'mid and small stones. i — Hvalfjordr 24 - i — Faxafjoidr, off Kollafjordr 10 - 2 spec. & 2 valve.s. — ,- — 8 — ii'/a - , ooze and stones. i — — , ca. 2 miles N. E. of Keflavik 19' 2 — 2072 - , ooze. 3 — — , 4.3 miles W. 3,'^ S. of Hel- gasker Vager 25 - r valve. All these are qnite small specimens; the largest (from the first locality) are only 12"'"'. long. So nth Iceland: Medalland Bngt 47—37 f"i- 5 spec These specimens reach a length of np to 33 mm The Faeroes. From earlier years we have several specimens of np to 53.5 '"". long, bnt the locality is merely given as "the Faeroes". In recent years M. nigra has been taken at the following places: Bordovig 7 — 10 fm., black sand, small stones, La- minaria. 18 spec. _ 10 - , sand with Laminaria. 5 — Kongshavn 5° " 9 ~ Vestmanhavn S'A— 5 - , fine black sand. i — 5 — 6 - , fine black sand. 11 — Trangisvaagfjord, head of o-i - i fragment. 9 miles E. S. E. of Bispen ca. 70 - 4 spec. Among the specimens from Kongshavn there are 2 which measnre 39.5 and 43.5""".; the re- mainder are only small specimens. The distribution is nndonbtedly circumpolar; Modiolaria nigra has been taken at arctic America (Northumberland Sonnd and Wellington Channel, Jones Sonnd and Rice Strait), West and East Green- land and Spitzbergen, in the Kara Sea, Polar Sea of Siberia and Bering Sea; towards the south it reaches to Cape Hatteras, Dogger Bank and western part of the Baltic, Sea of Okotsk and North-West America. — The vertical distribution extends from ca. 3—200 fm. Variation. Modiolaria nigra is subject to no small modification in regard to the form of the shell; as will be seen from the measurements below, the height of the shell in these 17 specimens alone varies from 48.3—58.1 °/o of the length of the shell and the breadth from 29.6—40.8% of the length of the shell. The Ingolf-Expedilion. 11. S- ^ 66 LAMELI.IBRANCHIATA. Locality West Greenland (Nanortalik) . East Greenland (Cape Dalton) . . — — (Turner Sound). Length of shell ( 46.5 ""• 132-5 - 40 - 35-5 - 35-5 - 34-5 - 44-5 - 31 - Iceland (Reydarfjordr) 67 43-5 The Foeroes (Kongsliavn) 41-5 - 39-5 - /5I-5 I 49 (Hveen) 42 (4^ I 37 Denmark (Hellebcek) — (Kattegat) Height of shell 25 '""\ 18 - 22 - 19-5- 20 - 18.5- 21.5- 17 - 33-5 - 22.5- 23 - 21-5- 29 - 26 - 23 - 21-5- 21.5- Height Length 53-8% 55-4 - 55 - 54-9 - 56-3 - 53-6 - 48.3 - 54-8 - 50 - 517 - 55-4 - 544 - 56-3 - 53-1 - 54-8 - 524 - 58.1 - Breadth of shell 14.5 '""\ II 14 - H-5 - 12.5 - 12.25 - 16 - 10.5 - 20.5 - 14 - 12.5 - 16 - M-5 - 14-5 - 14 - 11.25 - Breadth Length 31-2 % 33-8 - 35 - 40.8 - 35-2 - 35-5 - 36 - 33-9 - 30.6 - 32.2 - 31.6 - 31-1 - 29.6 - 34-5 - 34-1 - 304 - Mocliolaria faba (Miiller) Fabricius'). PI. Ill, fig.s. 8a~c. Mytibis faba Mitller, Prodr. Zool. Dan., 1776, p. 250; Fabricius, Fauna groenlandica, 1780, p. 419. — Modiola arctica Leach, in Ross, A voyage of discovery, 1819, App, II, p. 62. — Modiola faba M oiler, Index Moll. Groenlaudise, 1842, p. 19. — Modioki fiibiis Beck, Anitl. Ber. 24. Ver- samnil. detitsch. Naturf. u. Aerzte in Kiel, 1847, P- ^^y — Crriiclla deciissata Walker {iioii Montagu), Journ. Roy. Dublin Soc. Ill, i860, p. 72. — Modiolaria faba Beck, in Gainiard, Voyage de la Recherche, PI. 17, figs. 4a — i; Packard, Mem. Boston Soc. Nat. Hist. I, 1867, p. 280; Morch, in Rink, Dan. Greenland, 1877, p. 442^); Dall, Bull. U. S. Nat. Mus., XV, 1879, p. 146. — Crcnclla faba Jeffreys, Sc. Proc. Dublin Soc, N. S., II, 1880, p. 128; Bush, Proc. U. St. Nat. Mus. 1883, p. 244, PI. 9, fig. 3; Dall, ibid., 1886, p. 207; Pfeffer, Jalirb. Hamb. wiss. Anst., 3. Jahrg., 1886, p. 44. — Modiolaria faba Posse It, Medd. om Gronland, XXIII, 1898, p. 22. — Crcnclla faba Grieg, Rep. Sec. Norw. Arct. Exped. in the "F"ram", No. 20, 1909, p. 10, PL I, fig. I. The shell more or less ventricose, somewhat trapezoidal with a faint tendenc>- to be oval, truncate in front, anterior margin rather curved, obliquely rounded posteriorly, ventral margin faintly ') Of this little known species I give here a svnonyni3--list, which is complete, so far as I know; by far the most of references, howevei", are to tionnna mtda only. — I think it donbtful whether M. faba is a MotHohria, but it seems to me to stand further from the genus Crenella, and I retain the species under Modiolaria, therefore, to avoid founding a new genus on a single, northern species. =) Morch has forgotten to include the species in his earher hsts on the Mollusca of Greenland. LAMKLLIBRANCHIATA. 67 curved, dorsal side risscu in the middle and compressed, with the rather tumid and i^rominent umboiies lying at the front end. The valves fairly thin but strong, with a brownish or >ellowish, somewhat iridescent periostracum and provided over the whole with distinct, flatly rounded ribs, which to a number of ca. 50 radiate out from the unibones towards the circumference of the shell and are of the same breadth as or little broader than the intercostal furrows, but l)roadest towards the anterior end; the circular lines of growth very fine. Interior iridescent, usually pale-reddish or violet, crenulated at the margin; a crenulatiou of ca. 7 small teeth on the hinge-plate under and in front of the beak. Length up to 17.5 """. At West Greenland Modiolaria faba has been taken as far south as at Ivigtut (6i°i3' N. 1^.); it first appears in quantit}' at Godthaab (64''ii' N. I^.) and it is counnou further north, at least up to IMelville Bay. It is met with most frequently in shallow water (o — 15 fni., more seldom 20 — 30 fm.) and chiefly on stony, algae-covered clay bottom. — In Umanak F~jord I have found it attached by its byssns to sea-weed, which floated at the surface over very great depths. Distribution. Elsewhere the species is only known on the American side, namely: Cape Sabine in Smith Sound (78°45' N. L.), 2— 5 fm. and Havuefjord in Jones Sound (Grieg), Cumberland Soimd on Baffin Land (Dall, Pfeffer), as also from Labrador southwards to 5i°33'N.L., o— 15 fm. (Packard, Bush and DalP). Remarks. The numerous specimens at my disposal from Greenland show, that the form is variable to some extent, sometimes swollen and low, sometimes comparatively flat and high; to make this evident I have taken the measurements of the following specimens: jth of shell H( iight of shell Height Length Breadth of shi .11 Breadth Length 10 "'™. 7-5 "'"'■ 75 % 6.5 '""'. 65 7o 9 - 7 - 77.8- 5-5 - 61.1- 10 - 8 - 80 - 5 - 50 - 12 - 10 - 66.7- 5 - 41.7- In a manuscript left by the author of the Index Moll. Groenlandiae, H. P. C. M oiler, the following information is given regarding the animal: "The mantle is open in front for two-thirds of its extent; the jDosterior third is closed and forms a short conical tube, broad at the base. The hindmost part of the open mantle may extend a little out over the margin of the shell. The foot, when quite extended, is twice as long as the greatest length of the shell, otherwise quite similar in form to the foot in M. IcBvigata; extended whitish, contracted brownish, in \-oung specimens yellowish." MoUer writes further on M.faba: "The colour of the shell is dark chestnut-brown; the quite small specimens are clear lilac; those I have taken here in deep water and in the open sea, were greenish and very light-coloured .... It occurs on Laminaria in great quantity at Godthaab and further north along the coast; but I have also obtained it at a depth of 30 fm., 8 Danish miles from the coast." ■) Morch's record of its occurrence at the coasts of Denmark must be based on a mistake, as C. G. Joh. Petersen has already remarked i^Om de skalb. MoUuskers Udbredningsforhold, 1888, p. 128), as also Beck's statement that itlives at Iceland. 9* 53 I,AMELLIBRANCHIATA. Lastly, I may quote a remark by lajD. Steenstrup ') with regard to Modiolaria faba : "Eben dieselbe Lebensart (i.e. wie Mod. Ucvigata, cf. p. 6i) muss audi eiiie andere Muscliel aus derselbeu Abtheihuig der Gattung Modiolus, namlich der Alytilus faha Fabr. fn. gronl., fiiliren, deiin Prof. Steenstrup hatte mehrere in Spiritus aufbewalirte Kxemplare aus Gronland in ahnlichen Byssus- liiillen gesehen; die Hiillen waren durch aussere Faden theils an vSertnlarien- nnd Corallinen-Zweige gelieftet und ganz mit denselben bedeckt, theils waren sie zwischen verschiedenen Ascidien eingewebt, zum Theil selbst von den letztgenannten iiberwachsen". Crenella decussata Montagu. Mytilus dcciissatus Montagu, Test. Brit. Suppl., 1808, p. 69. — CrciicUa decussata Jeffreys, Brit. Conchol. II, 1S63, p. 133, PI. 28, fig. 6; Sars, Moll. Reg. Arct. Norv., 1878, p. 31, PI. 3, fig. 4. Modiola? ciccrcula Moller, Ind. Moll. Groenlandise, 1842, p. 19- — Crciiclla decussata var. Morch, Rink's Gronland, 1857, p. 94; Arctic Manual, 1875, p. 133; Rink's Dan. Greenland, 1877, p. 442. — Crenella decussata Posselt, Medd. om Gronland, XXIII, i8g8, p. 19; Hagg, Ark. f. Zoologi, Bd. 2, Nr. 13, 1905, p. 113; Jensen, Medd. om Gronland, XXIX, 1909, p. 329. The "'Ingolf has taken this species at: St. 129. N. W. of Iceland 117 fm. 6.5° C. i valve. 86. W. of Iceland (Brede Bugt). . . 76 - 4 spec. &: numerous valve.s. 87. - - — — — ... no - 12 — & numerous valves. The largest of these shells (St. 87) is 3.75 '""■. West Greenland. Here C. decussata is common from the southernmost parts up to a least Upernivik (72°47' N. L.). It occurs on clay and sand and among fragments of shells, most frequently at 20—50 fm. but also goes higher up (10 fm.) as well as deeper down (200 fm.). The largest specimens measure 5.5 """. — "It spins, but the threads are so fine, that they can scarcely be seen with the naked eye and even under the lens only in certain directions of the light" (H. P. C. Moller M.S.). East Greenland. A single specimen, 4.75 """. high, has been taken on the southern jjart of the coast at Ti- ningnekelak (65^56' N.L,.); according to Hagg (I.e.) a Swedish Expedition is .said to have taken a very small .specimen in Franz Josephs Fjord, the outer part of Myskokse Fjord, at iiG'/zfin- Iceland. When Morch wrote his review of the MoUnsca of Iceland he did not himself know Crenella decussata from the island, but was only able to report, that Jeffreys had seen a single specimen ') Extract in: Amtl, Bcricht iibcr die 24. Versaimnl. Deutsclicr Naturf. u. Aerzte in Kiel, 1847, p. 222. LAMELLIBRANCHIATA. 69 from there. From recent year's collections, however, C. dcctissata proves to be common all ronnd Iceland at depths of 6 — 50 fm. The following are the various localities where it has been found. East Iceland: L,6nsvik 40 fm., ooze and clay. i spec. & 3 valves. 0ster Horn 40 - 4 valves. Berufjordr, Djupivogr 6 - 100 spec. & 16 valves. — — 6 — 9 - , mud with black sand. i — Breiddalsvik 14 - 6 64°58'N.L., i3°25'W.L 40- 4 — & 25 valves. Vidfjordr 8—12 - 70 — & 70 — - 15 - 5 - Nordfjordr 40 - 2 valves Seydisfjordr at Skulavig 6- 7 spec. Bakkafjordr 12 — 15 - , black sand. 10 — «& 3 valves. — 32—25 - , clay and sand with shells. 5 - & 5 — — 52—43 ■ I — & 2 — Finnafjordr 18 - i valve. The maximum size is 4.75 """. North Iceland: Thorshofn 6 fm., mud. i valve. Vidarvik 11- 2 spec. & 3 valves. — 13V2 - , black sand. i valve. Axafjordr 3° ■ 1 sand and stones. 9 valves. Siglufjordr ^5 - 3 spec. & 3 valves. Skagastraud i spec. The largest of these specimens is 3.75 '""'. West Iceland: Isafjardardjup 60—63 ^'"- i spec. Dyrafjordr, inside Thingnaes 10 — 12V2 - , mud, small stones. 4 valves. Hvalfjordr 24 - 60 spec. & 140 valves. Krossvik 8 - , shell-gravel, blue clay, stones. 11 — & 4 — Faxafjordr 17 - , coarse shell-sand. i — «& 12 — — off Kollafjordr 8 — ii'/j - , ooze and stones. i — & 28 — — - — 10 - Several hundred spec. & valves. — mouth of Kollafjordr 9"/2 - 24 spec. & ca. 200 valv. -Q LAMELLIBRANCHIATA. Faxafjordr, mouth of Kollafjordr. . . g'/^— ii fni., fine black sand and ooze. 3 spec. & 4 valves. — Keflavik 15—16 - , fine black sand. 4 — & ca. 150 valv. — ca.2 miles N.E.of Keflavik ig'/j — ao'/a - , ooze. 2 — & - 100 — — 19 miles W. of Helgasker Vager 13 — 16 - , shell-gravel, stones & Lamin. 5 — & 8 valves. — 4.3 miles W. 3/^ S. of Hel- gasker Vager 25 - ca. 200 valves. — E. of Videy 9 — 10 - , fine sand and ooze. 2 spec. & 20 valves. — 7 miles N. N. E. of Ska- gens Light 17- 2072 - , sand and shells. i — & i valve. Hafuarfjordr 25 - , fine black sand and ooze. 2 valves. The niaximnm size of all these specimens is 4 """. South Iceland: Vestmannaeyjar 49 fm., clay with a little mud. 5 spec. & 60 valves. The maximum size is 3 """. The Faeroes. At the time when Morch prej^ared his Faunula Moll. Ins. Fa;roensium, CroicUa dcciissata was still unknown. During the investigations of recent years it has frequently been found at the Fa;roes, at a depth of ca. 5 — 5ofm.; the following are the different localities: Klaksvig 11 fm. 2 spec. & i valve. — 10—15 " 10 — & 160 valves. Bordovig 7 — 10 - black sand, small stones, Lam- ca. 300 spec. & numer- inaria. ous valves. — 10 - , sand with Laminaria. 60 spec. Ejde 5—6 - , coarse, black sand. 35 — '^ ca. 100 valv. Fundingsfjord 12 — ca. 20 - , coarse sand & clay. 80 — & - 200 — Kongshavn 12 — 16 - 10 ^ & 60 valves. 25-35 - I — — ca. 50 - 9 — & 160 — Vestmanhavn 31/2 — 5 - , fine black sand. Over 1000 spec. — 5—6 - , fine black sand. ca. 200 spec. & a num- ber of valves. — 10—30 - I spec. Sorvaag I4_i67^ - , ooze. i valve. Kalbakfjord 40-10 - 3 valves. Trangisvaag ^ .spec. 6i°4o' N. L., 7°4o' W. L 135 - i valve. 9 miles K. S. E. of Bispen ca. 70 - i — LAMELLIBRANCIIIATA. 71 16 miles E. by S. of south point of Nolso. . 80 fm. i spec. & 2 valves. 13 — W. by S. of Muiikon ca. 150 - 12 valves. The maxiniiim size of all these shells in only 3.5 ""^. Distribution. Crcnclla dcaissata is an arctic and boreal species, ranging in the north to Melville Bay ("Fox"), West and East Greenland, Spitzbergen (Tor ell and others), Nova Zeinbla (Leche), Kara Sea (Pfeffer) and Bering Sea (Kranse); in the south it reaches to Cape Hatteras (fide Dall, 1889), the British Isles M, Korea and California. In Danish waters it reaches to the southern Kattegat. The vertical distribution extends from 2— 300 fm. ; Jeffreys' statement, that it goes down to 1750 fm. probably rests on some mistake. According to my measurements the species becomes 5.5 "'"'. at Greenland, 4.75 """. at East Ice- land, 4 '""'. at West Iceland and only 3.5 '"'". at the Faeroes. The size thus decrease in the same pro- portion as the marine climate becomes milder. Cardiidae. Cardium echinatum Linne. PI. Ill, fig. II (young). Cardiuvi cchinatuiu Linne, Syst. Nat. ed. 12, i, 2, 1767, p. 1122; Jeffrey.s, Brit. Conchol. II, 1863, p. 270, PL 34, fig. 2. Cardiuvi (Acaiif/iocardia) ccliiiiatniii Morch, Vidensk. Medd. Naturh. Foreu. Kbhvn. 1867, p. 93. [Greenland]. Fabricius mentions'), that he had seen a weathered valve wa.shed up on the beach. Since then no one has found the species at Greenland and there is in fact not the least probability that it lives there. 3) Iceland. The .species, which was not known earlier from this island, has in recent years been found at several places on the south-western, southern and south-eastern coasts. South-West Iceland: Faxafjordr, off Kollafjordr S-ii'/^ fm., ooze and .stones. i spec. & 6 valves. — - — 10 - 3 - & 50 — — mouth of Kollafjordr 972—11 - , fine black sand and ooze. 3 — & 25 — — Keflavik 15 — 16 - , fine black sand. 4 — & 40 — I) According to Jeffreys the "Porcupine" ha,s taken Crenella decussala on Adventure Bank in the Mediterranean; thi.s statement seems all the more remarkable as the species is not mentioned either by French or ItaHan malacologists. ?) Fauna groenlandica, 17S0, p. 409. 3) Cf. also \V. H. Dall in Proc. U.S. Nat. Mus. XXIII, 1900, p. 3S8: "Cardium fchnwliim, O. Fabricius 17S0, from Greenland was doubtless derived from luirojiean ballast." -2 LAMELUBRANCHIATA. Faxafjordr, ca. 2 miles N. E. of Kef- lavik 19V2 — 20' 1 2 fm., ooze. 4 spec. & 24 valves. — , 4.3 miles W. 3/^ vS. of Hel- gasker Vager 25 - 13 valves. — , E. of Videy 9—10 - , fine sand and ooze. 4 — — , 7 miles N. N. E. of Ska- gens lyight 17 — 2072 - , sand and shells. i valve. Hafnarfjordr 25 - , fine black sand and ooze. i spec. &: 10 valves. These are on the whole small .shells; the largest is only 40""". long, and of the specimens containing the soft parts the largest is only 22 '""\ long. S o n t h Iceland: Vestmannaeyjar i spec. — 49 fm., clay with a little mnd. i fragment & 2 valves. S. W. of Eyjafjallajokul 17- 2 spec. — - — 23 - 15 — & 4 valves. 63°i7V2'N.L., i7°39'W.L 87 - , .sand mi.xed with ooze. i valve. Medalland Bngt 47 — 37 - 6 valves. The maximnm length of these specimens is likewise small, namely 38 '""'. S o u t h-E a s t I c e 1 a n d : Myre Bngt 58 fm., sand mixed with ooze. 3 valves. 64°i7.3' N.L., i4°44' W.L 45 - , black clay. i spec. & 4 valves. Lonsvik 40 - , ooze and clay. 7 — - 2 — The maximnm length of these is also only 40 "'"'. The Faeroes. Here the .species is common, at depths from ca. 5— Sofm., and reaches a considerable length, namely 57"'"'. The varions places where it has been fonnd are the following: Viderejde ca. 25 fm. 4 valve.s. Klaksvig 6—10 - 3 — Bordovig 7 — 10 - , black sand and small stones. 2 spec, and 6 valves. — 10 - , sand. 2 — Ejde ^ — 5 . ^ coarse black sand. 2 valves. Fundmgsfjord 12 — ca. 20 - , coarse sand and cla)-. 2 spec. & 20 valves. Skaalefjord 4_io - 4 valves. Kongshavn ca. 50 - 3 Vestmanhavu 3-14- 4 5~"6 -, black sand. 7 spec. LAMELLIBRANCHIATA. 73 Off Sandevaag. i spec. Sorvaag;, beacli. 7 — — 14 — 16'/2 fm., ooze. i — Kalbakfjord 40—10 - i2 valves. Thorshavn. 2 spec. Trangisvaag. 4 — — 15 - 7 valves. 13 miles S. of MyggenJEsholni ca. 70 - i valve. 16 — E. by vS. of soutli point ot Nolso - 80 - 2 spec. Distribution. Cardiiiiii cchiiiatxm is distributed along Europe from West Finmarkeu to Madeira and the Canary Isles, it reaches down to the south-western Kattegat and the Sound (Hveen). Towards the west it extends over the Fasroes to the south-eastern, southern and south-western coasts of Iceland. In the Mediterranean, including tlie Adriatic and Sea of Marmora, a variety 4 (var. iiiucronata) occurs. Its vertical distriliu- tion is ca. 5 — 80 fm. ') Remarks. The very small specimens of this species are not easy to recognize at first glance; as fig. 3 shows, the antero-dorsal "'^ j^ corner forms a sharp angle. During the „. ^ ,■ , ■ . ^ ^ *= Figs. 3—5- Carilium echuiatuin, ven,' young specimens, growth of the shell, however, the distance ^^^ appended cross indicates the natural size. between the "angle" and the beak becomes reduced (see figs. 4 & 5), so that the earlier, prominent corner now only appears as a tooth close in front of the umbo. Cardlum edule Liune. [Iceland.] Dr. A. C. J oh an sen has brought home a left valve of C.cdulc taken on the beach at Heimaey, which is the largest of the Vestmanna Islands at South-Iceland; the valve is thick-shelled and 33.5"""'. long. As the species has not been found elsewhere at Iceland, we must be careful in drawing con- clusions from this isolated find; this valve may have been brought to the i.slands with ballast or in other ways.^) [The Faeroes.J According to Morch (Vidensk. Medd. Naturhist Foren. Kbhvu. 1867, p. 93) C. rdiilc lives at the Fteroes, but from an examination of the specimens from the Fseroes labelled "Cardiuvi cdulc" 1) According to Jeffreys the Porcupine Expedition of 1S69 has taken it W. of Ireland down to 183 fni., but it is not stated whether the specimens were living or not. 2) Mohr's C. edule (Forsog til en Islands Historie, 17S6, p. 12S) is identical with CarJinm cilintiim Fabricius. The Ingolf-Expedition. II. i- ^O _. LAMELLIBRANCHIATA. by Morch and preserved in the Museum I have found, that this statement rests on a confusion with C.fasciatum Mtg. ') (of. p. 79 and figs, gf, g and h in PI. III). The species is thus not known from the Faeroes and must be omitted from tlie fauna Hst. Cardium minimum Philippi. Cardhim ruinwiniii Pliilippi, Enum. Moll. Sicil. I, 1836, p. 51; II, 1844, p. 38, PI. 14, fig. 18. — Cardium siteciciiiii Loven, Index Moll. Scand., 1846, p. 36. — Cardium iiiiniiiniiu Jeffreys, Brit. Conchol. II, 1863, p. 292, PI. 35, fig. 6. The "Ingolf has taken this small species at the following places: St. 98. W. of Iceland 138 fm. 5.9° C. 3 spec. & ca. 200 valves. - 86. - - — (Brede Bugt) 76 - i — ^ ^ valves. - 87. - - — — — no - I valve. - 10. - - — 788 - 3.5" - 2 corresponding valves. 8. S. W. of Iceland 136 - 6° - 3 spec. & 4 vahes. - 85. - - - — 170 - 50 — &. ca. 100 valves. 6. S. of Iceland 90 - 7° - 10 — & - 75 — [West Greenland.] According to Posselt^), there are 5 specimens of C. iiiitiiiiniii/ in the Riksmuseum of Stock- holm, labelled as taken by the Swedish Expedition of 187 1 at Kekertarsuak, which lies at Disko Fjord at 69'/2 N. L. I have had the opportunity of seeing one of these specimens and can confirm the correctness of the determination ; but on taking the general geographical distribution of the species into account, I feel convinced that some change in the label has taken place, and that the specimens in question do not come from Greenland. Iceland. The species was not known earlier from Iceland, Init in recent years it has been taken (besides at the "Ingolf stations noted above) at the following places: 63°i5'N. L., 22^23' W.L 170— 114 fm. ca. 1000 spec. 63°i8' — 21^30' — 94 - 10 — & 18 valves. 150 — & a number of 63°05' — 2o°7' — 293 - valves. Vestmannaeyjar 68 - 5 — 63°i7V2' N.L., 17^39' W. L 87 - , black sand with .shells i spec. & 4 valves. and stones. 63^42' N. L., 17^34' W. L 18-40 - 5 valves. ') Has Morch himself been in doubt as to the correctness of the (leterniinatioii, since he has not inchiiled C. rdi/h' in his suniniarj' at the end of his paper, or has he sini])lv forgotten? 2) Medd. om Gronland, XXIII, 1S9S, p. 60. I,AMICI,I,inRANCIIIATA. 75 l\I>Te Bugt 58 fni., sand mixed with ooze. i valve. Loiisvik 40 - , ooze and clay. 4 spec. &. g valves. C. iiiiiiiiinoii is thus fairh- conmion and even occurs in considerable nuuit)crs off the western and southern coasts of Iceland, at depths of 40 — 293 fni.'). The niaxiuiuni len>;th is 10""". The Faeroes. Nor was the species known from here formerl}-, but in recent years it has been taken at the following places: Fundingsfjord i2 — ca. 20 fni., coarse sand and clay. i spec. Vestmanliavn 5—6 - , fine, black sand. i — 6i°4o' N. L., 7°4o' W. L 135 - i — & 75 valves. 6i°i5' — 9°35' — ca. 475 - ca. 600 spec. 6i"'7' — 9°3o' — 440 - - 400 — 16 miles E. by S. of south point of Nolso 80 - i spec. Akralejte in N. 57 W., 12 miles 150 - 40 — & a number of valves. The sjjecimen from shallow water (Vestmanliavn, 5—6 fni. j is very small (2 """.); at the other localities the species reaches a length of 7 — 9 """. Large numbers still occur at a depth of 475 fm. Distribution. Cardiiim i/iiiiiiiuii/i is distributed along Europe from the North Caj^e to Gibraltar, also in the Mediterranean; through the Kattegat it reaches down to the north coast of Funen and the Sound; over the Fteroes it extends to the south and west coast of Iceland. It has been taken at depths of 10 — ca. 800 fm. Cardium fasciatum :\Iontagu. PI. Ill, figs. 9a-k. Cardium fasciatum Montagu, Test. Brit. SuppL, 180S, p. 30, PI. 27, fig.6; Jeffreys, Brit. Conchol. II, 1863, p. 281, PI. 35, fig. 3. Cardium fasciatum Morch, Vidensk. Medd. Naturh. Foren. Kbhvn. 1867, p. 93; ibid. 1868, p. 220. — Cardimii edule Morch (non Linne), ibid. 1867, p. 93. The "Ingolf" has taken this species at: St. 98. W. of Iceland 138 fm. 5.9° C. 2 valves. . 86. - - — (Brede Bugt). . . 76 - 4 spec. & 80 valves. - 87. - - — — — .■■ no - ca. 70 valves. These valves are up to 11 mm [West Greenland. I According to Posselt^) there are 2 specimens of this species in the Riksmuseum of Stock- holm, which are stated to have been taken at Julianehaab in southern West Greenland. I feel cou- ') A single specimen indeed has been taken at a depth of 7S8 fm. ("Ingolf' St. 10), but it was dead. 2/ Mcdd. om Gronland, XXIII, 1S98, p. 60. 10* 76 LAMELLIBRANCHIATA. \anced, however, for the same reason as that given under the preceding species, that some mistake or other has occurred, and that C. fascia turn does not Hve at all at Greenland. Iceland. From the west coast it is present from many localities, and in some cases in fairly large numbers, so that we may say that it is common there; it seems also to be fairly common on the south coast; it occurs in smaller numbers and at comparatively few localities on the north and east coasts, which is also quite natural, as these coasts have a relatively cold marine climate')- The depths at which the species has been taken lie between ca. lo — 120 fm. The maximum length is 15 "'"\ The various localities are as follows. East Iceland: Myre Bugt 26 f m. 2 valves. Seydisfjordr off Brimnes 40 - i valve. Bakkafjordr 32 — 25 - i spec. The largest specimen is 9.5""". long. North Iceland: Thistil Fjordr 50 fm., clay with many stones. i valve. Axafjordr 22 - , mud. i — Skjalfandi Bugt 31 - , very fine black sand. 2 spec. Husavik in E. 4 miles 42 - i — 0fjord at Svalbardseyri 10—20 - 1 — Skagastrand Bugt 119 - , mud. i — Kollafjordr 10 - i — Veidileysa 21 — 25 - i — The largest of these specimens is 12 """'. long. West Iceland: Ouundarfjordr 10 fm. 7 spec. & 7 valves. — ca. 12 - ca. 100 spec. Dyrafjordr. 7 spec. & 5 valves. — inside Thingnses lo'/a — 12'/2 - , mud and small stones. 50 — & ca. 30ovalv. Fossfjordr. i spec. Talknafjordr. 6 — N. W. of Talkni. i spec. & 3 valves. Brede Bugt, off Hellissaudur 20 - i \alve. Krossvik 8 - , shell-gravel, blue clay, stones, i — 0 It has to be remembered, however, that not so many collections have been made at the other coasts as on the west coast. i.ami;lubranchiata. 77 Faxafjordr. 12 spec. & 20 valves. ~ , 17 fm., coarse shell-sand. 4 valves. — , 14—29 - 2 — — , off Kollafjordr 8 — ii'/j - , ooze and stones. 5 — — ,- — 10- I spec. & 34 valves. — , mouth of Kollafjordr g'/a — 11 - , fine black sand and ooze. 5 — & 9 — — , Keflavik 15 — 16 - , fine black sand. 4 — & 80 — — , 2 miles N. E. of Keflavik 19' 2 — 2o'/2 - , ooze. i — ■ & 44 — — , I niileW.ofHelgaskerVager 13—16 - , shell-gravel, stones. i valve. — , 4.3 miles W. 3/^ S. of Helga- sker Vager 25 - 5 spec. & 80 valve.s. — , E. of Videy 9 — 10 - , fine sand and ooze. 2 — & 7 — — , 7 miles N. N. E. of Skagens Light 17 — 20^/2 - , sand and shells. 4 valves. Reykjavik. 3 spec. & 9 valves. Reykjavik Roads. i spec. Hafnarfjordr ii'/a - i — — 25 - , fine black sand and ooze. 1 — & 9 valves. Skagi 21 - I — One of these specimens is 15™"'. long, a second 14.5""". and several are 10 — 13""". long. South Iceland: Heimaey, beach. 2 valves. Vestmannaeyjar 30 fm., shell-gravel. i spec. & 7 valves. ^^ ^ — 49 - > clay with a little nmd. 16 — & 160 — ^^ S. W. of Eyjafjallajokul 15—18 - i valve. 63°i7V2' N. L., i7°39' W. L 87 - i spec. p. 63°24'N.L., 17^5'W.L 70- I — V- The largest specimen is 11.5"'"'. Faeroes. From these islands we have numerous specimens and valves from many localities, so that it must be considered conmion both near the coast and out to sea; living .specimens have been taken in depths of ca. 5—135 fm. It may attain a considerable size, namely up to 19"'"'. and is not rarely 14—16"'"'.; in deep water, however, just as at Iceland, it seems to have a smaller size. The localities are as follows : Viderejde 10 fm. i valve. Bordovio' 7 — 10 - , black sand, small stones. 2 valves. Ejde 5 — 6 - , coarse black sand. 36 — Fundingsfjord 12 — ca. 20 - , coarse sand and cla\-. 8 spec. & 42 valves. 78 LAMELLIBRANCHIATA. Skaalefjord 4—5 f'"- 2 valves. Kongsliavn 12 — 16 - , sand and ooze. 14 spec. & 17 valves. — 25 — 35 - I valve. — ca. 50 - 10 spec. & 45 valves. Vestmanhavn 3''2— 5 -, fine black sand. 2 — & 3 — — 5—6 - , — — — I _ & 2 - Sorvaag i^—iS^U - , ooze. 2 — & 9 — KoUefjord. i — Thorshavn. 2 — — , onter roads 12 — 16 - 2 valves. Nolso, deep hole at north end ca. 100 - 2 sjjec. & 8 valves. Trangisvaag. Nnmerous spec. & — 5 miles N. by E. of Myggenses east point 50 - i valve. 13 — S. of Myggensesholm - 70 - 50 valves. 6i°4o' N. L., 7°4o' W. L 135 - 2 spec. & 1 1 valves. 6 miles N. by W. of Kalso 60 - i valve. 1^/2 — 2 miles off the mouth of Bordovig 20 — 30 - i spec. 16 miles S. of south point of Nolso . . ca. 80 - 5 — 16 — E. by S. of south point of Nolso - 80 - i — & 4 valves. Akralejte in N. 57 W., 12 miles - 150 - 2 valves. 13 miles W. by S. of Munken - 150 - 40 — Distribution. C.fasciatum is distributed along the whole of Europe, from the western part of the Murnian Coast to the Canary Isles and the Eastern Mediterranean; through tlie Belts it reaches down into the Western Baltic. Towards the west it extends to the Fseroes and Iceland. G. O. Sars estimates the vertical distribution to be from 10 — 180 fm.'), but at the Fseroes it reaches up to 5 fm. (cf. above), according to Spar re Schneider it comes into 3 fm. (at Tromso) and according to C. G.J oh. Petersen into 2 fm. in the southern Kattegat. Remarks. Cardiuin fasciafuin appears to be a very variable species at Iceland and the Fseroes. It occurs in two forms: a. The shell short, strongly ventricose, with the posterior area sloping quickly downwards and as if abruptly separated from the middle area by a keel (PL III, figs. 9a — b). b. The shell somewhat elongated (especially posteriorly), not much tumid, with the middle area grading without sharp boundary into the posterior area (PI. Ill, figs, gc — d). Between these extreme forms, however, there are transitions. So far as my experience goes, the tumid variety is usually an oceanic form, whilst the elongated and flat variety is found in fjords; but both may be found together in the latter 2). ') Jeffreys states, that the "Porcupine" has taken it W. of Irehmd at a depth of SoS fni., but as usual without stating whether living specimens or dead shells were found. But the statement itself is perhaps erroneous. -) Whilst the tumid form is predominant at Iceland and the Faeroes, I find the flat form by far the coiiimouest in LAMELLIBRANCHIATA. 79 Tlie contour changes from the ol)Hquely cordiform or quite triangular (see PI. Ill, fig. gi; just as in C. rxiguum) to become broadly oval or almost circular. There is also great variation in regard to the sculpture. Sometimes for example, the ribs may be rough with scales and pointed tubercles not only on the anterior and posterior area, but the middle area may also be partially or wholly beset with scales or tubercles; in this way we obtain a form such as that figmcd in I'l. Ill, fig. 9c, the sculpture of which resembles thai in C. iindnsuiii, but transitions show, that it can be traced back to the common form C.fasciahnii with smooth, central ribs. In the young, with contour like that of C. exigutiiii^ the posterior ribs arc beset with very ]5ointed and comparatively long spines. The ribs are usually quite flat and only separated by a fine line, but ven,' often the interspace between them is somewhat broader, yet never so broad as the ribs themselves. Sometimes, however, the ribs are more or less convex, especially when they are separated b\- a distinct interspace. Not rarely an intercostal sculpture is seen under the lens in the form of a fine pricking (PL III, fig. 9k). I have further represented (PI. Ill, fig. 9f, g and h) that form of C.fasciatuvi , which was con- fused by Morch with C.rdiile; the resemblance is striking, indeed, but the pointed tubercles on the posterior ribs (PL III, fig. 911) reveal its true nature — in C.cdiiie the rugosities are lamelliform here. Cardium nodosum Turton. [Faeroes], To this species Morch (Vidensk. Medd. Naturh. Foren. Kbhvn. 1867, p. 94) refers 7 specimens from Thorsha\-n in the Fteroes. I have not been able to find these specimens here in the Museum, and as the species is not present in the considerable collections, which have been made at the Fteroes in recent years, I think it vcr\' doubtful, if the species occurs there. Possibh-, an unusually well sculptured form of C.fasciatuiii (cf. above and PL III, fig. 9e) has given rise to the confusion. Cardium ciliatum Fabricius. PL III, fig. 10 (young). Cardium ciliatitiii Fabricius, Fauna groenl., 1780, p. 410. — Cardiitii/ islaudicitiii Chemnitz, Conch. Cab. VI, 17S2, p. 200, PL 19, fig. 195 — 96. ') -- Cardiuui puhfscois Co u th o u y, Boston Journ. Nat. Hist. II, 1838, p. 60, PL 3, fig. 6 — Cardium arcticuiii Sowerby, Proc. Zool. Soc. 1840, p. 106; Conch. Illustr., 1841, fig. 26. — C«;7//>//// //(7j)r.f// St im pson, Proc. Acad. Nat. Sc. Philadelphia, 1863, p. 58; Packard, Mem. Boston Soc. Nat. Hist. I, 1867, p. 278, PL 7, fig. 14. — Cardium islandicum Gould & Binney, Rep. Invert. Mass., 1870, p. 139, fig. 450. — Cardium ciliatuin Sars, MolL Reg. Arct. Norv., 1878, p. 46, PL 5, fig. 4. Cardium cdulc Mohr (non Linne), Forsog til en Island.sk Naturhistorie, 1786, p. 128. — Cardium islandicum Moller, Index MolL GroenL, 1842, p. 20. — Cardium ciliafuiu Morch, Rink's the material collected from Denmark; it is onlj- among the specimens from the Kattegat that there are some which resemble the ventricose, keeled form from Iceland and the Faeroes. I) Chemnitz is the autlior of the name Carduiin islandicum, not Linne, as the species first occurs in the 13th Ed. of Syst. Nat, pars 6, 1792 (p. 3252) and with a reference to Chemnitz' work of 17S2. By erroneously referring the name C. islatidicum to the 12th Ed. (1767) of Linnei Syst. Nat. (though no Cardium of that name occurs there), several older authors have got the present species renamed "Cardium islaiidimm Linne"; this error appears again in Kobelt's Prodr. Faun. Moll. Test. Mar. Eur. (1880). 3q LAMELLIBRANCHIATA. Gronland, 1857, p. 92; Vidensk. Medd. Naturli. Foreu., 1868, p. 220; Arctic Manual, 1875, p. 132; Rink's Dan. Greenland, 1877, P-44^; Posselt, Medd. om Gronland, XIX, 1895, p. 70; ibid. XXIII, 1898, p. 57; Hiigg, Ark. f. Zoologi, Bd. 2, 1904, No. 2, p. 51; Jensen, Medd. oni Gron- land, XXIX, 1909, p. 352. The ''Ingolf has taken this species at: St. 113. Norwegian Sea 1309 fm. i valve, of a very small spec. - 104. — - 957 - I small spec, dead bnt with connected valves. 98. W. of Iceland 138 - 5.9° C. i spec, (yonng). West Greenland. Here the species is very common from the sonthernmost part of the coast at least np to Upernivik; fnrther north, it has been taken in Melville Bay ("Fox"), and on the American side it has been fonnd as far north as at Grinnell Land in Dobbin Bay (79°4o' N. L-). It occnrs most freqnently on clay bottom and in moderate depths (10—80 fm.), bnt is also found both on hard and quite soft bottom, as also in greater depths (100 — 280 fm.). The largest specimen is 65""". long. East Greenland. It has been taken here at 5 localities, from Angmagssalik to Mackenzie Ba)- (65''35' — ca. 73'// N. L.) and in depths of ca. 10 — 40 fm. The largest specimen is 62 """. long. Iceland. On the north coast Cardiiiiii ci/iafiii/i is very common, as also on the east coast (at least down to Berufjordr") and on the north-west coast; on the south-west coast it lives in Hvalfjordr^); on the south coast it has not been found. It keeps especially to clay and sand mixed with clay, but is also found where there is ooze. The depths vary from 6—85 fm., but are most frequently 25—50 fm., the young however being comparatively frequent in more shallow water; on the other hand, the "Ingolf took a very young specimen (living) at 138 fm. (cf. above). The maximum length is 74""". The various places where the species was found are as follows. East Iceland: Myre Bugt 58 fm., sand mixed with ooze. i spec. Lonsvik 40 - , ooze and clay. 4 — & 10 valves. Berufjordr 6 - , mud with black sand. 2 — — mouth 54—41 - , ooze. 27 — Breiddalsvik 14 - , sand. 3 — Faskrudsfjordr 50 — 20 - , blue clay. 24 — ') On the boundary to the south coast it has been taken in Lonsvik and Myre Bufjt, but only as small and dead specimens. 2) It has also been taken at various places out in Fa.xatjordr (ef. the following list), but only as dead specimens and valves. IvAMEIJJHRANCHIATA. 8i Reydarfjordr 48 fin. — •■•• 50 - - 68 - - 74 - — 86 - Outer Reydarfjordr 68 — 80 - Vidfjordr Nordfjordr Mjofifjordr, head of fjord. Seydisfjordr 15 40 , ooze and clay. , mild. 9-5 - — 26—50 - — 40 - Mouth of Seydisfjordr 38 — 14 - — - — ca. 40 - , .stomach of haddock. Seydisfjordr 60 — 30 - — Hanefsstadeyrar 10 — 2 - Lodmiindarfjordr 30—23 - , ooze. Bank off Lodmundarfjordr 38 — 47 - 65°42' N. L., i3°57' W.L 60 - Vopnafjordr 6 — 12 - Bakkafjordr 7 - — 12-15 - — 20—28 - — 32—25 - — 20—52 - — 52-43 - Off Midfjordr 35—5° - Finnafjordr 18 - As ah'eady mentioned, the specimens from the two southernmost localities are small; from Myre Bugt there is only a verj- small specimen (1.5 "''".), which besides was dead; and from Lonsvik the specimens are likewise dead, though of a fresh appearance and of at most 22.5 "'"'. in length. But from Berufjordr already the species becomes common, the specimens being up to 50™". in length. The largest specimen taken on the east coast is 73 "'"'. black sand. clav mixed with sand. I spec. & I valve. 5 - 8 — & 12 valves. I — & I — I — 2 — I — 3 valves. I spec. I — 14 - 3 - 23 - 9 - I — I — I — I — I — 2 — I — 12 — 4 - 7 — 30 - & 35 valves. 12 — I — I valve. North Iceland: Thistil Fjordr 10 — 24 f'"-) sand and "coral". — — 27 — 28 - , sand with mud. . — — 50 - > clay with many stones. Thorshofn 6 - The Ingolf-Expediiion, il. 5. I valve. 4 spec. & 3 valves. I valve. I — 82 LAMELLIBRANCHIATA. Vidarvik 13V2 fm., black sand. Axa^ordr 22 - , stones and shells. — 22 - , mild. — 25 - , ooze. — 30 - , sand and stones. Skjalfandi Bugt 21 - , black sand. — — 31 " ) very fine, black sand. Husavik in E. 4 miles 42 - — in E. by S 47—58 - Ofjord. — , west side of Oddeyri 5 — 9 - From stomach of Hippoglos- Hofdi 6~i2 soides platessoides. — , at Svalbardseyri 10—20 - — , Aknreyri 17 - — , jnst S. of Hrisey 18 - , clay. — , S. of Hrisey 17 — 20 - , stones and mud. KoUafjordr 5 - Skagastrand. The largest specimen is 74 ^"\ long. I spec. & 3 valves. I — II — 3 spec. &: 2 valves. 5 valves. 4 - 1 spec. 2 — 3 - 3 - 8 — I — I — 1 — 2 — I valve. 1 spec. 2 — West Iceland: Skutulsfjordr 5—13 f™. i spec. Onnndarfjordr 10 - 2 — ca. 1 1 - 6 — — - 12 - 6 — Dyrafjordr. n — , inside Thingnaes lo'/j — 1272 - , mud and small stones. 12 valves. 65°52' N.L., 23^58' W. E 33 - I valve. Fossfjordr 44- 6 spec. Talknafjordr. a — ca. 25 - I — N. W. of Talkni. i _ Grundarfjordr. i _ Hvalfjordr 24 - 20 spec. & 75 valves. Krossvik 8 . ^ shell-gravel, bine clay, stones, i fragment. Faxafjordr, off Kollafjordr 8— ii'/^ - , ooze and stones. 14 valves. 1" — 10- 5 spec. & 34 valves. — , month of Kollafjordr 9V2— n - , fine black sand and ooze. 2 — & 40 — — , Keflavik 15 — 16 - , fine black sand. 30 valves. LAMELLIBRANCHIATA. 83 Faxafj6rdr,ca.2 iiiilesN.E.ofKeflavik ig'/j— ao'/z ^i"-, ooze. 18 valves. — , I mile E. N. E. of Helgasker Vager 11' 2 - i spec. — ,4.3 miles W. ^;'^S. of Helga- sker Vager 25 - 5 valves. — ,E. of Videy 9—10 - , fine sand and ooze. i spec. & i valve. — ,ca. I' J miles N. W. ■ , N. of Engey Baake ^9 - ) shells and stones. i — Reykjavik. 3 valves. — , Engey 7 — S'/a - , ooze. i spec. & 2 valves. Hafuarfjordr 25 - , fine black sand and ooze. i — & 20 — From the sontli-west coast (region of Faxafjordr) only separated valves or dead (empty) specimens are represented, though the}- often appear quite "fresh", with well-preserved ligament and periostracnra ; the maximum length is only 53"'"'. Hvalfjordr is however an exception from what has just been said, as living specimens have been taken there, the largest of which is 14"'"'. long; a much larger, but dead specimen appears quite "fresh" and the largest of the separated valves is 61 "'"'. long. On the north-west coast the species thrives well and reaches a length of Jt,'""'. [Faeroes.] A valve has been taken .south-west of Sydero (6i°9'N.L., 7°54' W.L.) at a depth of 180 fm., but it is quite small (3.75 "'"'.) and looks ancient (fossil). The species does not live at the islands. Distribution. Cardium ciliatum is a high-arctic and circumpolar species, as it occurs, apart from West and East Greenland and northern Iceland, at Spitzbergen, in the Barents Sea, at Nova Zembla and in the Kara Sea, in the Polar Sea of Siberia, Bering Sea, at Sitka and in the Wellington Channel; the southern boundary for its distribution lies at Cape Cod (Da 11), East Finmarken (Sars and Friele), northern Japan and Puget Sound (Dall). Remarks. The shape of this species varies a good deal, as will be seen from the accompan>ing measurements of 4 specimens from Iceland: Length Height 73 "'"'• 67 72 - 71 71 - 64 65 - 58 Height Breadth Breadth Length Length 91.8 % 48 """. 65-8 7o 98.6 - 40 - 55-6 - 90.1 - 42-5- 59-9 - 89.2 - 33 - 50.8 - The very small .specimens (see PI. Ill, fig. 10) can only be recognized as belonging to this species on comparing them with somewhat larger specimens because the dorsal margin forms an angle with the anterior margin. The young thus obtain some resemblance to those of C. cchinatiiiii (of. p. 73 and PI. Ill, fig. n), but are easily distinguished by the fact, that the radiating ribs are more numerous, g LAMBLLIBRANCHIATA. ca. 27 (against ca. 19 in C. cchinatuiii) and have a much finer spination; further, the posterior margin rises ahiiost vertically (in C. cckinatnin on the other hand tlie posterior margin bends forwards). Cardlum elegantulum (Beck) Moller. Cardium elcgatiiulum (Beck) Moller, Index Moll. Groenl, 1842, p. 20; Gould & Binney, Rep. Invert. Mass., 1870, p. 141, fig. 451; Sars, Moll. Reg. Arct. Norv., 1878, p. 47, PI. 5, fig. 5. Cardium elegantulum Morch, Rink's Gronland, 1857, p. 92; Vidensk. Medd. Natnrh. Foren. 1868, p. 220; Arctic Manual, 1875, p. 132; Rink's Dan. Greenland, 1877, p. 441 ; Posselt, Medd. om Gronland, XXIII, 1898, p. 56; Jensen, ibid. XXIX, 1909, p. 352; Odhner, Ark. f. Zoologi, Bd. 7, No. 4, 1910, p. 19. West Greenland. The species has been taken here at several localities, from Julianehaab (60=43' N. L.) to Upernivik (72''47'N.L.); it keeps mainly to clay bottom and depths of 20-ioofm. It reaches a length of 15"'™. East Greenland. The Danish Expedition of 1898—99 took a specimen of 12 ""'. in length at 65°39' N. L., namely at Tasiusak, 20 — 30 fm., stony ground with sparse algal vegetation. Iceland. It has only been taken here at some few jjlaces and only on the north-eastern part of the island (between Berufjordr on the east coast and Thistil Fjordr on the north coast). The various places are as follows: East Iceland: Mouth of Berufjordr 54—41 fm., ooze. 3 spec. & 6 valves. Off Borgarfjordr 80 - 2 valves. The largest specimen is 12""". long. Odhner (I.e.) also records some few specimens from Berufjordr. North Iceland: N. of Langanes 70 fm. i spec. Thistil Fjordr 50 - i valve. The largest specimen is 9.5""". long. Odhner (I.e.) records further a young specimen from Thistil Fjordr, 10— i6fm. Distribution. C. clcgantulu))i is an arctic species, which is found, apart from West and East Greenland and North-East Iceland, only at north-western Norway (to Tromso) at depths of (lo) 15— 127 fm. (Sars, Sp.-Schneider, Friele & Grieg)")- — It has been found as fossil by M.Sars at ') Both G. O. Sars and H.J. Posselt give the east coast of N.America as habitat for this species, but this is un- doubtedly a mistake; both of these authors have probably assumed that Cardium elegantulum is American, because it was in- cluded by Gould in his work on the Invertebrates of Massachusetts (I.e.), but Gould does not give any American locahty, only Greenland. Nor have I been able to find the species as .\merican in other lists of Packard, Dall, Bush, Whit eaves etc. ; thus, it is only mentioned as from Greenland by W. H. D a 1 1 in his "Synopsis of the I"am. Cardiidce and of the North American Species" (Proc. U. St. Nat. Mus. XXIII, 1900, p. 386). LAMELLIBRANCHIATA. 85 Christiaiisund in western Norway, by W. C. Brogger at Cliristiaiiia (in tlic "yonn<;cr Area-clay") and by Knipowitsch at Dwiiia. Remarks. Measurements of some specimens show, tliat tlie sliape is more or less variable : LeiifTth of shell Height of shell lireailth of shell 12.5 """. 11-25 """• ^ " "'• 12.5 - 10 - 8 - 12 - 11.5 - 9.5- 12 - 9.5 - 7-5- ICardium norvegicum Spengler.] Worch has shown already (Vidensk. Meddel. Naturh. P'oren. Kbhvn. 1867, p. 94), that Jeffreys' reference to this species as Fceroese (Brit. Conchol. II, 1863, p. 296) is due to a misunderstanding. Cardium (Serripes) groenlandicum Chemnitz. PI. Ill, figs. 12a— b (young). Cardiiiin groenlandicum Chemnitz, Conch. Cab. VI, 1782, 1x202, PI. 19, fig. 198. — Cardiuiii horeale Reeve, Conch. Icon. II, 1844—45, Sp. 131, PI. 22, fig. 131. — Cardmiii fabricii Deshayes, Proc. Zool. vSoc, 1854, p. 333. — Aphrodite groenlandica Gould & Binney, Rep. Invert. Mass., 1870, p. 144, fig. 454; Sars, Moll. Reg. Arct. Norv., 1878, p. 49, PL 5, fig. 3. Vcnits islaudica Fabricius (non Linne), Fauna groenl., 1780, p. 411. — Cardium groenlandicum :\Ioller, Index Moll. Groenl., 1842, p. 20; Beck, in Gaimard, Voyage de la Recherche, PI. 15, fig. I— 15; Morch, Rink's Gronland, 1857, p. 92; Vidensk. Medd. Naturh. Foren., 1868, p. 221 {\2.x. solida) ; Arctic Manual, 1875, p. 132; Rink's Dan. Greenland, 1877, p. 441 ; Friele, Nyt Mag. f. Naturvidensk., 24 Bd., 1879, p. 222; Becher, Osterr. Polarst. Jan Mayen, 1886, III, p. 70; Posselt, Medd. om Gronland, XIX, 1895, p. 70; ibid. XXIII, 1898, p. 55; Jensen, ibid. XXIX, 1909, p. 353; Hagg, Ark. f. ZooL, Bd. 2, 1904, No. 2, p. 50. The "Ingolf has taken this species at: vSt. 113. Norwegian Sea 1309 fm. A fragment of a left valve. . iig. - loio - A fragment of a right valve. West Greenland. The species is one of the commonest Molluscs here, from the southernmost part of the coast at least up to Upernivik ; further north it has been taken by the "Fo.\" in Melville Bay and by the "Fram" on the American side in Rice Strait (78°45' N. L.). It keeps mainly to soft (clay) bottom and to depths of 10— 5ofm. It may attain a length of no""". East Greenland. It has been taken here at 9 localities, distributed from Angmagssalik to Sabine Island, with depths of ca. 7— 25 (40) fm. The largest specimen was 70'""'. long. 86 LAMELLIBRANCHIATA. Jan Mayen. The Norwegian Nortli-.Vtlantic Expedition of 1877 took numerous, small specimens at 10— 2ofm., the Austrian Polar Exped. of 1883 17 specimens up to 62 "'"'. long at a depth of 10 fm. The Danish Expedition of 1900 also took several specimens up to 62 "'"'. long, but all empt>', at depths of 55 and 50—60 fm. Iceland. The species is very common on the north-west, north and east coasts (down to Berufjordr); on the south-west coast it lives at any rate in Hvalfjordr; it has not been found on the south coast. It keeps to soft bottom and depths of ca. (41 6— 6ofm. The largest specimen is 92"'"'. long. The various localities are as follows. East Iceland: Hornafjordr, beach. i spec. Berufjordr 35 — 22 fm. i — Djupivogr 6 - , mud with black sand. 9 — — 10 - , stones. 2 — Breiddalsvik 14 - , sand. 2 spec. & 3 valves. Faskrudsfjordr 50—20 - , blue clay. i spec. Eskifjordr 20 - i — Vidfjordr 15- i — Seydisfjordr. 18 — — , between the bridges on north side of fjord. i — — , Brimnes 4- i — — , at Skulavik 6 - , black sand. i — — 31—15 - 4 — — 38—14 - , mud. I — — 20 — 50 - I — — , mouth ca. 40 - , stomach of haddock. i — Bank off Lodmundarfjordr 38 — 47 - t — Vopnafjordr 6- 2 — 6—12 - I — Bakkafjordr 12-15 - , black sand. 7 — — • 32 — 25 - , clay mixed with sand. i valve. Finnafjordr 18 - 5 spec. The specimen from the southernmost locality, Hornafjordr, is empty and only 8.5""". long; but from Berufjordr northwards the species becomes common and reaches a considerable size (maximum length 92 """.). The specimen from the shallowest depth, 4 fm. namely, is young (only 15.5 """. long), but already at a depth of 6 fm. the species reaches a length of 89""". LAMELUBRANCHIATA. 87 N o r t h I c e 1 a 11 d : Thistil Fjordr 25 fin., sand. 3 spec. Thorshofn, I'/a miles from mouth of liver 6 - , sand. i — Hagauesvik 3'/2 — 4 - 2 • — Husavik in E. 4 miles 42 - 4 valves. — in E. by S 47—58 - 3 spec Gfjord at Svalbardseyri 10 — 20 - i — — Hofdi 16 — 12 - 3 — Siglufjordr 15 - i — Skagafjordr, Miklavatn in Fljotum .... 5 — 6 - i — It is due naturally to incomplete collections, that so little of this species is present from the north coast. The specimen from the shallowest depth (4— 3' , fm.) is only 28""". long, but that from a depth of 6 fni. is 86.5 "'"\ West Iceland: Lonafjordr zy^U — 30 fm. i spec. Isafjardardjup 60 — 63 - i — Amarnes 5 — 7 - 2 — 0nundarfj6rdr. 2 — - ca. 9 - I — - 10 - 6 — - - 10 - 35 - - - 12 - 3 — - 12-14 - 7 - Dyrafjordr. 4 — — , inside Thingnses 10— 12"2 - , mud and .small stoue.s. 33 valves. Fossfjordr 44 - i valve. Talknafjordr. 3 spec. Pati-iksfjordr. i — Grundarfjordr. 8 valves. Olafsvik. 3 — Hvalfjordr 10— 12 - i spec. & 3 valves. — 24 - 10 — — , Hvammsvik 10—12 - , black ooze. 2 — — - ii'A— 12 - 3 — Faxafjordr, Kollafjordr 8 - , fine sand and mud. i — — , mouth of Kollafjordr g'/z - 7 — & 40 valves. — , — - — .... 9Y2-11 - , fine black sand and ooze. I — & 22 — — , off Kollafjordr 8— 11V2 - , ooze and stones. i — &; 30 — 88 LAMELUBRANCHIATA. Faxafjordr, off Kollafjordr lo fm. ca. 25 spec. & 100 valves. — , Keflavik 15-16 - i — & 2 — — , ca. 2 mil. N.E. of Keflavik 19V2-20V2 - , ooze. i — E. of Videy 9 — 10 - , fine sand and ooze. 3 — Reykjavik, Engey 7— S'A - , ooze. i fragment of a valve Hafnarfjordr. i valve. — 25 - , fine black sand and ooze. i — On the northern part of the west coast C. groruhDidiciiiii is common and reaches the consid- erable length of 80™"'. As the above list shows, a con.siderable material has also been collected on the southern part of the west coast (region of Faxafjordr); we might think, therefore, that the species is also common on this part of the coast. It must be emphasized, however, that the living specimens hitherto taken from the bottom of the sea are usually small (2—12"'"'. long), and that the separated valves accompanying them most often have an "ancient" appearance and do not reach any great length either (at most 43 ''™. long). From this, however, Hvalfjordr, with the Hvammsvik lying on its south side, again forms an exception, as very large specimens have been taken here (up to 79™"'. in length) and containing the animals. The specimen from Keflavik is also of a fairly good size and, though empty, appears rather "fresh". Distribution. Cardimu groenlandicum is a high-arctic and circumpolar species; its southern boundary lies in the Atlantic at Cape Cod (Dall) and Varanger Fjord (G. O. Sars)') and Porsanger Fjord (Friele), in the Pacific at Hakodade and Puget Sound (Dall). Remarks. However well-characterized this species may be against all the other northern Cardiidcr, it nevertheless shows a series of variations. This is especially evident in quite young specimens. In regard to sculpture some are radially furrowed only on the posterior area, the majority likewise on the anterior area, some even over the whole shell. Some are quite flat, others greatly ventricose and transitions occur. Some are uniformly coloured, whiti.sh, straw-yellow, gray or brownish, others again have dashes of yellowish-red. Adult specimens vary especially in regard to form. Some are high, short and greatly ventricose, others comparatively elongated and flat, as will appear from the accompanying measurements: Height Breadth Localit}' Length Height T Breadth ; ;- ' " ^ Length Length Berufjordr (Iceland) 90"'"'. 77 "'"'. 85.6% 50"'"'. 55-6% Jakobshavn (Greenland) . . 85 - 7^ - 83.5 - 5° - S^-^ ■ Djupivogr (Iceland) 75 - 59.5 - 79.3 - 35 - 46.7 - Tunugdliarfik (Greenland) 73.5- 57 - 77.6 - 34 - 46.3 - 0nundarfj6rdr (Iceland) . . 71 - 59.5 - 83.6 - 37 - 52- 1 - Godhavn (Greenland) .... 70 - 62 - 88.6 - 42 - 60 - I) .\t this place, however, only small specimens have been taken, according to Sars I.e. LAMELLIBRANCttlA^A. 89 Both Morcli and Posselt lia\c noticed tliat the species is variable. The former remarks: "The Icelandic specimens are nnich more thick shelled and elongated than those from Cireenland". Posselt modifies the last part of the sentence in the following statement: "Tlie variety nhlonga, which is the commonest form at Iceland, is met with here and there at South Greenland". So far as I can judge, there is no such connection between the geographical distribution and the outer form of the animal; the variation seems rather mdividual. In any case, Morch's statement is erroneous in regard to the first point and greatly exaggerated as to the second. In PI. Ill, fig. 12 a I have represented a small specimen of the strongly scul])tured, youthful form, which might possibly give rise to difficult}- in the determination, if it occurred isolated. Further, for the sake of comparison I give a comparatively smooth specimen (PI. Ill, fig. 12b), on which, however, as usual the prodissoconch is strongly sculptured. Isocardiidae. [Isocardia cor Linne.] Posselt has introduced this characteristic Bivalve into the fauna of Greenland. In the vStock- holm Museum he found, namely, a fragmentar>- valve, 70 " "'. long, taken according to the label by the Swedish Exped. of 1871 at 63°35'N. L., 52°57'W.L. and a depth of 43 fm. "To judge from the discovery of the dead valve, it ma}' be taken as probable, that Isocardia cor lives in the Davis Strait", writes Posselt •). W. C. Brogger ^), on the other hand, has pointed out, that Isocardia cor, which is a southern (Lusitanian) form, at the present time to be considered a great rarity on the Norwegian coasts, is certainly extinct at Greenland, and that the fragment mentioned by Posselt must in all probability have belonged to a fossil specimen. As I.cor does not occur at the Faeroes, nor at Iceland, which have a much milder marine climate than West Greenland, and as it does not occur at North America either, I also think it quite improbable that it lives on the banks in the Davis Strait. During a visit to the Stockholm Museum I came to the conviction, that an exchange of label had probably taken place, and that the valve referred to had not been taken at Greenland at all. In any case Isocardia cor should be struck out of the Greenland fauna. Cyprinidae. Cyprina islandica Linne. Venus islandica Linne, Syst Nat. ed. 12, i, 2, 1767, p. 1131. — Cyprina islandica Jeffreys, Brit. Conchol. II, 1863, p. 304, PI. 36, fig. 2; Gould & Binney, Rep. In v. Mass., 1870, p. 129, fig. 443. Cyprina islandica Morch, Rink's Gronland, 1857, j). 92; Vidensk. Medd. Naturh. Foren., 1867, p. 94; ibid. 1868, p. 221; Arctic Manual, 1875, p. 132; Rink's Dan. Greenland, 1877, p. 441; Posselt, Medd. om Gronland, XXIII, 1898, p. 61. 1) Medd. om Gronland, XXIII, 1898, p. 54. 2) Brogger: Om de senglaciale og postglaciale nivaforandringer i Kristianiafeltet, igoo -01, p. 591. The Ingolf-Expediiion. II. 5. 12 go LAMELLIBRANCHIATA. The "Ingolf has taken this species at: St 86. West Iceland (Brede Bugt) 76 fm. 6. S. E. of Iceland . 90 A spec. 13 "™. long and 3 valves of small specimens and fragments of a larger specimen. A fragment (with sharp edges) of a large specimen. [West Greenland]. The Copenhagen Zoological Museum contains: a. 2 corresponding valves, 43 "'"'. in length, taken according to the label at Jakobshavn by Dr. Rudolph; on this basis C.islaiidica was for the first time recorded as belonging to Greenland in Morch's list of 1857. The periostracum is preserved; there is no trace of soft parts and the valves bear distinct marks of having lain in a mass of sand mixed with clay. b. I right valve"), 37 ""'. long-), taken according to the label by the malacologist H. P. C. Moller (thus about the middle of last century) in "Davis Strait, 7—8 miles from land". Thus, living specimens are not known from Greenland, and it seems to me inconceivable, that a Bivalve such as C. islandica could possibly have escaped attention, if it now lives anywhere at Greenland In the first place, its size is considerable, so that it is not likely to have been overlooked, as the Danish part of the West Greenland ma\- be said to have been well-investigated, so far as the coastal belt is concerned. Further, we must remember, that C. islandica is frequently washed up on the beach, near which it lives; but C. islandica is not found either among the large number of washed-up shells, which have been brought home from Greenland. These facts seem to me to indicate quite definitely, that C. islandica does not now live at Greenland; the "dead" shells mentioned above may be taken to have been "sribfossil", unless some change of label has taken place in the course of time. In any case Cyprina islandica should be omitted from the Greenland fauna. Iceland. The species is to hand in large numbers from the east, north, west and south coasts, so that it is probably common all round the island J). Adult specimens have been taken at depths of 4— 3ofm. 4), the young down to 76 fm. It lives chiefly on sandy bottom or sand mixed with clay, but may also be met with on clay bottom. The maximum length is 105 "'"'. Faeroes. Here the species is quite common, on sandy bottom or sand mixed with clay, and reaches a length of iio"'"\ Adult specimens have been taken at depths of 5 — 5ofm., the young down to 70 fm. ') This single valve is erroneously given in Posselt as "2 spec". 2) It is consequently misleading, when the length is given as 120 "'m. in Consp. Faunas groenlandicae. 3) I omit stating the various places where it has been found, as the material at hand consists for the most part of young and small specimens, whilst adults are rarely brought home, owing to the large space they take up. 4) On the south and south-east coasts, however, large empty shells have been taken at several places at greater depths, down to 90 fm. LAMELLIBRANCHIATA. 91 Distribution. On the North American side Cypn'nn islaudica occurs from Cape Hatteras to the Newfoundland Bank and the southern part of the Gulf of vSt. Lawrence '). On the European side it is distributed from the south-west of France (Arcachon) to the Murmau Coast and White Sea^); towards the west it reaches over the Faeroes to Iceland; from the Kattegat it reaches into the Sound and through the Belts down into the south-western Baltic 3). Cypriva islaudica is consequently, as I have already more fully shown on an earlier occasion t), a distinctly boreal form, a result that Prof. Brogger has also come to from a consideration of its late immigration into southern Norway 5). The vertical distribution is ca 4— 5ofni., but the young may be met with in greater depths''). In geologically very late (postglacial) deposits it has been found as far north as at vSpitzbergen, which indicates that the climate of that time was somewhat milder than it is now?). Remarks. Gould & Binney write regarding Cyprina islaudica (op. cit. p. 131): "It is subject to ver>- little variety". This does not agree with the experience I have gained on going through a number of specimens from Iceland and the Fjeroes. I find, that the three dimensions of the shell may vary considerably, as will be seen from the measurements given below. Height Breadth Locality Length Height Breadth — ^ 6 6 Length Length Reykjavik 105 ■""-. 93 "•". 88.6 % 61.5 ""■. 58.6 7„ Vestmanhavn 104.5 - 89 - 85.2 - 51 - 48.8 - Keflavik 102.5 " 83.5 - 81.5 - 58 - 56.6 - Seydisfjordr 102 - 78 - 76.5 - S^ " 5° " Reykjavik 99 - 82 - 82.8 - 57 - 55-8 - 0nundarfjordr 98.5 - 82 - 83.2 - 50 - 50.8 - Vidarvik 93 - 88 - 94.6 - 52 - 55.9 - 1) Posselt (I.e.) gives it from Labrador and Packard as his authority, but it is not mentioned in the latter's "View of the recent Invertebrate Fauna of Labrador" (Mem. Boston Soc. Nat. Hist, vol.1, Part U, 1867, p. 262), nor in the later lists of the MoUuscau fauna of Labrador by W. H. Dall and Katharine Bush. The northern boundary for its occur- rence at N. America is fixed, I find by the following statement of Wliiteaves: ".Although recorded by Fabricius as a Greenland shell, this species has not yet been found in the Gulf of St. Lawrence, north of the Bale des Chaleurs" (Catal. of the Marine Invertebrata of Eastern Canada, p. 130; Geol. Sur\-ey of Canada, 1901). W. is not right however in his reference to Fabricius' Venus islandica (Fauna groenlandica, 1780, p. 4"), as this is obviously not identical with Linne's Vemis (Cyprina) islandica, but with Cardium { Serripes) groenlandicum Chemnitz. 2) Cat tie states, that it has also been taken in the eastern (the "cold") part of the Murman Sea |Les LanieUibran- ches du "Willem Barents". Bijdrageu tot de Dierkunde, 18S6), but Knipowitsch has never found it there (Zur Kennt- niss der geol. Gesch. der Fauna des Weissen und des Murman-Meeres, p. 24. Verhaudl. Kais. Russ. Mineral. Gesellsch. St. Petersburg. 2. Sen, Bd. XXXVIU, No. i), so that it must be in any case extremely rare. 3) In his lists showing the distribution of the MoUusca taken by the Swedish Expeditions of 1875 and 1876, Leche has given C. islandica as occurring in the Bering Sea (K. Sv. Vet-Akad. Handl. Bd. 16, No. 2, 1S78, p. 81), and this statement appears again in Posselt (L c); some mistake in writing or printing must have crept in here, as the species is not mentioned in any of the lists published by Dall, Crosse, Edg. Smith or Krause on the MoUusca of the Bering Sea. 4) Ad. S. Jensen: Studier over nordiske MoUusker. II. Cyprina islandica. Vidcnsk. Medd. naturh. Foren. Kbhvn., 1902, p. 33. 5) Br5gger: Om de senglaciale og postglaciale nivaforandringer i Kristianiafeltet, 1900—01, p. 573. 6) A. C. Johansen has shown, that smaU (young) specimens can be met with even in the abyssal region, as Jeffreys' statement of the occurrence of C. islandica \V. of Ireland down to 1215 fm. refers to quite small individuals (Vid. Medd. Naturh. Foren. Kbhvn., 1901, p. 44). 7) a. my paper on Cyprina islandica I.e. and Jensen & Harder in: "Postglaziale Klimaveranderungen, Stockhohn 1910, p. 400. 12* 92 I^AMELl/IBRANCHIATA. Astartidae. Astarte borealis Chemnitz. PI. IV, figs. I a— f. Venus borealis Chemnitz (partim), Conch. Cab. VII, 1784, p. 26, PI. 39, fig.412 (non fig.s. 413— 414'). — Tridonta borealis Sars, Moll. Reg. Arct. Norv., 1878, p. 50, PI. 5, fig. 8^). Astarte arctica Moller, Index Moll. Groenl., 1842, p. 19. — Astarte seinisiilcata Morch, Rink's Gron- land, 1857, p. 92; Vidensk. Medd. Natnrh. Foren., 1867, p. 95; ibid. 1868, p. 222; Arctic Mannal, 1875, p. 132; Rink's Dan. Greenland, 1877, p. 441. — Astarte borealis Posselt, Medd. om Gronland, XIX, 1895, p. 71, PI. I, figs. 8—12 (yzx. sericca Poss.); ibid. XXIII, 1898, p. 61; Jensen, ibid. XXIX, 1909, p. 335. The "Ingolf has taken this species at: St. 33. Davis Strait 35 fm. i living, i dead .spec, and i valve. - 35. — — 362 - I valve of a yonng spec. - 86. W. of Iceland 7^ - 8 valves of yonng spec. - 124. N. - — 495 - I valve. - 125. - - - 729 - I - - no. N. E. of — 781 - 4 valves (corresponding). -120. — - — 885 - 4 — — - 116. S. of Jan Mayen 371 - 4 — — - 1 17. - - - — 1003 - I valve. - 113- - - - — 1309 - I — West Greenland. A. borealis is common along the Danish part of the coast; fnrther north, it is fonnd at Port Foulke on vSmith Soimd (Hayes), on the American side even at Dnmbbell Harbour at 82°3o' N.L,. ("Alert & Discovery"); the bottom-soil is mud, sand and clay. The depths recorded lie between 5— 5ofm. 3). The maximum length is 44""". East Greenland. Here the species has been taken by Danish, Swedish and German Expeditions at quite a dozen places on the stretch from Angmagssalik to Shannon Island (ca. 65°3o'"75°3o' N. L.l, in depths of 3 — 40 fm. The maximum length is 44 '^"'. 'I Fig- 413 obviously represents Astnrte creiiata Gray, fig. 414 A. sulcata d. C. =) A fairly detailed synonymy-list for this species of many names is ^iven by Kobelt; Prodr. Moll. Test. Mar. Enrop., 1888, p. 394. M As will be seen, the species is certainly taken in the Davis Strait at the considerable depth of 362 fm., but as the shell ni question is of a young specimen, the occurrence cannot be considered as normal LAMELLIBRANCHIATA. 93 Jan Mayen. A. borealis has been taken here by the Norwegian North-Athmtic Expedition at io~i5fm. (Friele), the Austrian Expedition at 65 — 90 fni. (Becher, sub. uom. A.borcalis Cli. and A.producta So\v.| aud the Danish Expedition of 1900 at 15 and 50 fm. Iceland. On the west coast a large number of specimens liave been taken at many localities, so that the species must be common here. From the north coast and especialh- from the east coast, on the other hand, we have A. bnrcalis onl>- from a few places and it would thus seem to be comparatively rare in these parts of Iceland. — It occurs on sand, clay and mixed bottom-soil; the depths recorded for living specimens lie between 3 and 31 fm. The maximum length is 47""".') The various localities are as follows. East Iceland: Berufjordr, Djnpivogr 10 fm. 2 valves. Seydisfjordr, at Skulavig 6 - , black sand. i spec. Lodmundarfjordr ca. 20 - , from stomach of haddock. i ~ Gunnolfsvik. 7 valves. These few occurrences might indicate, as mentioned, that A. borealis is comparatively rare on the east coast; and we can hardly consider it due to chance, that this species especially has not been taken by the collectors, when a species of similar size and occurrence such as A. elliptica is to hand from the east coast in large numbers and from rather many localities |cf. p. 109). On referring to Dr. A. C. J oh an sen, who has explored the coasts of Iceland, this zoologist has kindly given me the following information, which agrees well with what has been said above: "In my notes from Iceland I find Astarte borealis recorded from the beach at vSeydisfjordr, but not from Bakka^ordr, Berufjordr or Hamarsfjordr. As I have noted it from the beach on the south-west and west coasts, from \'estmannae>jar, Reykjavik, Stykkisholmr and Arnarfjordr, this would indicate, that it is commoner on the shores of the south-west and west coasts than those of the east coast". It mav however be added, at the same time, that Nils Odhner, who has only had a relat- ively small material at his disposal for his paper: "Marine Mollusca of Iceland"^) is able, nevertheless, to record A.borcalis from a locality on the east coast, namely: Berufjordr 9-30 fm- Many spec. The largest of our specimens is 44™"'. long, of Dr. Od liner's 46 mm North Iceland: Thistil Fjordr 10—24 ^m-, sand and "coral". 5 spec. Vidarvik iS'A - , black sand. 6 spec. & 5 valves. 1) Some separate valves, which are only labelled "Iceland", reach however a much larger size, namely 52—56 2) Arkiv for Zoologi, Bd. 7, 1910, No. 4. mm _. LAMELLIBRANCHIATA. Axafiordr 30 fm., sand and stones. i spec. Skjalfandi Bugt 31 - , fine black sand. 1 — Husavik Z'A-io - i valve. 0fjord I — Skagastrand i — Odhner I.e. records it as taken at: Raufarhofn 30 fm. Many spec. The largest of the specimens to hand is 40 """. long. The same almost may be said regarding this part of the coast as about East Iceland; we might have expected to find A. borealis very common on the north coast, and it is thus remarkable that there is so little material from there. West Iceland: Hofnvik 10 fm. 3 spec. Adalvik S'A^Q " 2 — Hesteyrarfjordr 15 — 1772 - 5 valves. Isafjordr 3 spec. & i valve. — , beach. i — &. i — Skutilsfjordr i .spec. 5-13 - I - 0nundarfj6rdr ca. 9 - 2 — Dyrafjordr 3 — — , inside Thingnses . . 10— la'/z - , mud and small stones. 4 valves. 65"56'N.L., 24°3o'W.L 37 - 2 - Arnarfjordr, beach. 2 — Talknafjordr 2 spec. 65°32' N. L., 24°38' W.L 22 - , stones. 3 — Stykkisholmr, beach. i valve. Grundarfjordr i spec. & i valve. Olafsvik I — Hvalfjordr 5 — 13 - i valve. — 24 - I — Krossvik 8 - , shell-gravel, blue clay, stones. 5 spec. &. 20 valves. Faxafjordr 15 — 16 - , fine black sand. i — & 2 — — 17 - , coarse sand. 2 — & 14 — — 14 — 29 - 3 valves. — 25 - I valve. — , mouth of Kollafjordr 972—11 - , fine black sand and ooze. 4 spec. & 17 valves. — , off Kollafjordr 8 — 1172 - , ooze and stones. 6 — & 9 — LAMELLIBRANCHIATA. 95 Faxafjordr, i mile E. N.E. of Helgasker ii'/iim. — ,1 — W. of Helgasker... 13—16 - , shell-gravel and stones. — , 7 miles N. N. E. of Skagens Light 17 — 20'/ 2 - , sand and shells. Reykjavik — , beach. — 8 - — (Engey) ?— S'A - , ooze. Hafnarfjordr — 3-4 - , ooze. The largest specimen is 47 """. long. I spec. 10 valves. spec. & 10 valves. 3 — I — & 3 South Iceland: Vestmannaeyjar, beach. — , harbour '^ — o fm. — 30 - . gravel. — 49 - ) clay with a little mud. — , Heimaey, beach. 63°2i' N.L., i7°3i' W.L 69 - , black sand. 63°2i' — I7°i5' — 58 - , sand, stones, shell-gravel. 63°42' — i6"32' — 29 - The largest specimen is 39 "'"'. long. 5 spec 7 — 3 — & 3 valves. I valve. 3 spec. & 23 — I valve. I — 3 spec. [The Faeroes.] Landt recoTds " Venus borealis" as "taken at the bottom of Vestmanhavn Fjord"'), and Morch states, that a very large specimen of Astarte sevnsulcata Leach was received from the pastor P. Holm, who had collected at the Fseroes^). As A. borealis has not been found however during the extensive investigations of recent years, these records probably are mistakes, and I believe myself entitled to remove A. borealis from the fauna of the Faeroes, unless certain records are forthcoming. Remarks. At Iceland and Greenland Astarte borealis is very variable, both in regard to form and sculpture of the shell and the structure of the periostracum. Periostracum. On the Icelandic specimens the periostracum may form a thin layer, smooth or finely fibrous towards the margin, or it may be somewhat thicker and as if frayed; the smooth periostracum is most frequently fairly light-coloured, yellowish-brown and somewhat glistening, the fibrous kind is darker, brown or almost quite black. In the West Greenland .specimens the periostracum varies in the same way. In all my specimensfromEastGreenland the periostracum is brown to swarthy, thick and bast-hke. 1) Landt: Forsog til en Beskrivelse over Faeroerne, 1800, p. 289. 2) Morch L c. 1868, p. 95. 96 LAMELLIBRANCHIATA. It seems as if the iDeriostracum were thickest and most frayed in arctic specimens, as this characteristic is seen not onlv in the specimens from East Greenland (and in part those from West Greenland [and Iceland]), bnt also in (my) specimens from Spitzbergen and the Kara Sea'). Scnlptnre. The shell may be, apart from the fine lines of growth, quite smooth or more or less distinctly folded, at the nmbones only or more or less far down on the shell. The folds sometimes appear as fine and dense, sometimes coarser ribs with wider intervals, and these ribs may sometimes in the adult specimens reach at least halfway down on the shell. Form. At Iceland the form is relatively high and more or less convex, as will be seen from the following measurements: Height Breadth Locality Length Height ^^^^ Breadth ^^^^ Vestmannaeyjar 44 -"'. 38 "'™. 86.4 °/„ 17 "'"'. 38.6 °/„ Reykjavik 43 - 36.2 - 84.2 - 17.75 " 4i-3 - — 42 - 34 - 81 - 15.5 - 36-9 - — 38 - 33-5 - 88.2 - 17 - 447 - Faxafjordr 37 - 32.25 - 87.2 - 14-25 - 38-5 - — 36-5 - 32-5 - 89 - 16 - 43.8 - — 34-75 - 29 - 83.5 - 16.5 - 47-6 - Seydisfjordr 44.25 - 34.25 - 77.4 - 20.25 - 45.8 - At West Greenland similar forms occur, but here also — though apparently not very fre- quently along the more southern (Danish) part of the coast — we find a greatly compressed form (var. placenta Morch^) = Astartc Ricbardsoni Reeved), of which I ma\- give the following measurements as example: Height Breadth Locality Length Height ^^^^ Breadth ^^^ West Greenland 39 ""'\ 31 ™". 79-5 °L 12.25 '"™. 31.4 7o At East Greenland we find more or less compressed, often strikingly elongated forms i) as will be seen from the following measurements: Height , , Breadth Locality Length Height -^^^^ Breadth — ^-^^ Turner Sound 44 "'"'. 35 """. 79-5 % ^8 "'"'. 40.9 % - — 40 - 30 - 75 - H-25 - 35-6 - Tasiusak 32.5 - 27.2 - 83.7 - 13- 40 - — 29 - 24.5 - 84.5 - 10.5 - 36.2 - Hekla Havn 29 - 21.5 - 74.1 - 9-5 " 32-8 - Forsblads Fjord 27 - 20 - 74.1 - 8.25 - 30.6 - ') C. G. Joh. Petersen's statement regarding A.borealis in Danish waters seems to me of interest in this connection: "the epidermis is here (i.e. in specimens from the Belts and Baltic) much more frayed than in the Kattegat specimens'' (Det vidensk. Udbytte af Kanonbaaden Hauch's Togter, 1893, p. 75). Compare also in this connection A. Krogh: "The tension of carbonic acid affecting the structure and preservation of moUuscan shells''; Medd. om Gronland, XXVI, 1904, p. 387. 2) M5rch: Catal. des Moll, du Spitzberg. Mem. Soc. Malacol. Belgique, T. IV, 1869, p. 22. 31 Reeve in Belcher: The last of the Arctic Voyages, II, 1855, p. 397, M- 33, fig- 7- 4) For such specimens Posselt (I.e.) has set up a special variet}-, sericea, on account of the elongated form of the shell, the thick epidermis and its silk-like sheen; in my opinion it cannot be kept separate from the variety //uc'V/te Miirch. LAMELLIBRANCHIATA. 97 The followins^ figures on PI. lY nia\- serve as illustrations of the above-nieutioued, \'arying form and structiu-e iu Asfar/f horcdlis: iMg. la represents a specimen without folds and with an almost smooth (fibrous only at the margin), fairlv light-coloured periostracuni. The shell is rather convex, as is seen from fig. r b. Western Iceland. Fig. ic represents a very high form, with quite narrow folds on the uppermost part of the .shell and with fairly thick, fibrous periostracuni on the lowest part. Western Iceland. Figs, id and le represent a strongly compressed form [\i\x. placciitd Morchi with distinct folds on the uppermost part of the shell. Western Greenland. Fig. if represents a very elongated form [\-2iX.scricea Posselt). East Greenland. Distribution. Astnrfe borealis is an arctic and circunipolar sjiecies. In Norway it is said not to live south of Bergen'), nor has it been taken living in the Skager Rak or Northern Kattegat; but after this break in its distribution it appears again in the south-western Kattegat and reaches through the Sound and Belts, increasing in numbers but decreasing in size, down into Kiel Ba}- and thence south of Lolland to a little east of Bornholm (C. G. Joh. Petersen). It is said to occur in the middle of the North vSea-), but empty shells only have been found at Scotland, the Hebrides and Shetland. On the American side the southern boundary lies at New England, in the Pacific at Alaska, the Aleutians and Kamschatka. — - Its bathxinetric distribution is 3 — 26ofm.i|. Astarte Montagu! DiUwyn. PI. IV, fig.s. 2 a— c. Venus couiprrssa (non Linne) Montagu, Test. Brit. Suppl , 1808, p. 43, PI. 26, fig. i; (Asfarfc) Forbes S: Hanley. Hist. Brit. Moll., I, 1853, p. 464, PI. 30, fig. i; Jeffreys, Brit. Conchol., II, 1863, PI. 37, fig. 3. — I'f/ms Montagui Dillwyn, Descript. Catal. Regent Shells, I, 1817, p. 167. — Nicaiiia Baiiksii Leach, Ross' Voyage of Discovery, 1819, Append, p. 62; »Sars, Moll. Reg. Arct. Norv., 1878, p. 51, PI. 6, fig. i. — Nicania striata Leach, I.e. p. 62. — Astarte globosa M oiler, Inde.x Moll. Groenl., 1842, p. 19; Reeve, Belcher's Last of the Arctic Voy- ages, 1855, p. 398, PI. 33, fig- 6. — Astarte Wartianii Hancock, Ann. Mag. Nat. Hist, vol.18, 1846, p. 336, PI. 5, fig. 15—16. — Astarte pulcfiella Jonas, Philippi, Abbild. u. Beschreib. neuer Conchyl., II, 1847, p. 60, PI. i, fig. 12. — Astarte fabula Reeve, I.e. p. 398, PI. 33, fig.5+)- Astarte Banksii'hloW^x, Index Moll. Groenl., 1842, p. 19; Morch, Rink's Gronland, 1857, p. 20; Vidensk. Medd. Naturh. Foren. 1S68, p. 223; Arctic Manual, 1875, p. 132; Rink's Dan. Greenland, 1877, p. ,441; Posselt, Medd.om Gronland, XIX, 1895, p. 73, PI. i, fig.s. 1—4; ibid. XXIII, 1898, p. 68; ') C. G.J oh. Petersen's reference to it as living in Christiania Fjord lOni de skalbierende Molluskers Udbrednings- forhold, 1888, p. 461 is based on a mistake, caused by -■isbjornsen; Brogger has explained (Om "de senglaciale og post- glaciale nivaforandringer i Kristianiafeltet, 1900 -or, p. 581), that Asbjornsen's '\-l.semisukata" was not A.borealis but a form of A- elliptica. 2) Schrader: Lamellibranchiaten der Nordsee (Inaug.-Dissert.), 1910, p. 43. 3) As a rule the bouudarv is placed at a depth of ca. 6ofni., but greater depths — down to 260 fni. — are recorded by Friele & Grieg (Norw. Xorth-.\tlantic Exped., MoUusca III, 1901, p. 24) from .Spitzbergen. 4) For further references to the extensive .synonymy see Kobelt: Prodr. Moll. Test. Mar. Europ., 1S88, p. 395, under Aitnrtc Blinks:! Leach. The Ingolf-Expcdition. II. ;. ^3 g LAMELLIBRANCHIATA. Jensen, ibid., XXIX, 1909, p. 333. — .ij/r?;-/r j/;-/rt/rt Moller I.e., p. 20; Morch I.e. 1857, p. 20; 1875, P- 132; 1877, p. 441. — Astartc pulchella Moreh, I.e. 1857, p. 20; 1875, p. 132; 1877, p. ^\. — Astartc Montagui Morch, Vidensk. Medd. Xaturh. Foren. 1867, p. 95; ibid. 1868, p. 223. The "Ingolf" ha.s taken A. Afotitagiii at the following plaees: St. 35. Davis vStrait 362 fm. i valve. - 33- - ^ 35 - 2 valves. - 86. W. of leeland (Brede Bugt) .... 76 - 30 — - 87. - - — — — .... no - 2 — - 104. N. E. of Iceland 957 - 4 — - 113. S. E. of Jan Mayen 1309 - 5 — Remarks. In the figures 2 a — c on PI. IV I have compared 3 specimens, which seem to me to illnstrate the main types of this very variable species within the faunistic region dealt with here. Fig. 2a represents A. Montagui Dillw. typica. a short and high, somewhat triangular form; the anterior end is a little elongated-rounded, the posterior end shorter, strongly sloping downwards, truncate; the umbones lie a little behind the middle of the shell. Fig. 2b represents A. Moniagtti Dillw. var. striata (Leach) Sars, a more elongated form, which stands midway between the foregoing and the following. Fig. 2c represents A. Montagui Dillw. var. Warlianii Hancock, the shell of which is elong- ated, elliptical, in general rounded both in front and behind; the umbones lie almost in the middle of the shell. The measurements of the three specimens, which I have chosen as types, are as follows: Height Breadth Length Height Breadth Length Length A. Montagui typica 14 """. 13 """. 92.9 % 7-5 "'™- 53-6 ° 'o — vsiY. striata 15 - '^2> ' 86.7 - 8 - 53.3 - — - Warhaini ... 22 - 16.75 " J^-i - 9-5 - 43-2 - These three forms are not at all sharply separated, however; all transitions may occur. In discussing the separate geographical regions further opportunity will be taken to mention the variab- ility of this species. West Greenland. Here the species is common, from the southernmost parts up to Cape York; on the American side it has been taken as far north as 8o°N.L. It occurs most frequently at dej^tlis of 5— 5ofm., but is also met with at greater depths. At West Greenland the variety striata is by far the most predominant, and along with it occurs rather frequently the variety glohosa IMoller, which is characterized by an extremely tumid form; the typical form and the variety Warhavii are comparatively rare. At the same time it must be remembered, however, that all possible transitional stages exist between the forms mentioned. LAMIU.MHRANCHIAT.^. 99 The maxiiiiuin length i.s 23 '""'. The measvirements of some speciinens will illustrate the fonii-relatioii among the \-arieties mentioned. . Montagiii typica : Length Hei 20 "'"\ 18.5 16 - 15 15 - 14 14 - 13 12.8 - 12 Height Length Breadth Breadth Length 92.5 °/o II.5 "'". 57-5 'Vc 93-7 - 9-25- 57-8 - 93.3 - 9 - 60 - 92.9 - 8.25 - 58.9 - 93-8 - 7-25- 56.6 - A. Montagui x&r.globosa. 17 - 15 88.2 - II 64.7 - 14.5 - 12.75 - 85.2 - 9-5 - 65.5 - ii.S - "•5 - 97-5 - 8.2 - 69.5 - "■5 - 10.5 - 91.3 - 7.2 - 62.6 - "•5 - 11.25 - 97.8 - 8 - 69.6 - 10.5 - 10.25 - 97.6 - 7-25- 69 - ^i. Montagui var. striata: 23 - 19.8 - 19 - 17 15 19.75 - 85.9 16.75 - 84.6 16.5 - 86.8 16 86.5 14.75 - 86.8 13 86.7 12 52.2 - 9-5 - 50 9-25- 50 8.5 - 50 8 - 53-3 A. Montagui var. Warhami : 19 - 15 78.9 17.75- 14 78.9 14.5 - 11.25 - 77.6 12.75- 9-75 - 76.5 9-25- 48.4 9 - 50-7 7 48.3 6.5 - 51 East Greenland. Here A. Montagui has been taken at 15 localities between Angmagssalik and Sabine Island (65°4o'- 74°32' N. h.\ at depths of 3—50 fin. The largest specimen is 24.2 '^"'. long. The majorit}- of the specimens at hand belong to the variet\' Warhami, in a form which is generally rather compressed but is sometimes rather tumid; the variation in this regard will be seen from the accompanying measurements. 13* lOO LAMELLIBRANCHIATA. A. Montagid van Warhami: Length Height 24.2 """. 18.5 23-5 - 16.5 23 - 18 22.5 - 18 22 17-25 22 16.75 20.5 - 1575 20.5 - 15-5 20.5 - 16.5 20 16 Height Length Breadth Breadth Length 764 °/o 8.25 mm 34-1 °/c 70.4 - 8.5 - 36.2 - 77.8 - 975 - 42.2 - 80 - 12 - 53-3 - 78.4 - 875 - 39-8 - 76.1 - 9-5 - 43-2 - 76.8 - 8.5 - 41-5 - 75-6 - 8 - 39 - 80.5 - 9 - 43-9 - 80 - 10 - 50 - The concentric ribs frequently reach right down to the ventral margin, but other specimens are only ribbed on the umbonal region or to the middle of the shell, showing on the rest of the shell only fine lines of growth (= Astarte fabula Reeve). Some few specimens belong to the variety striata, which in my opinion — as already mentioned — is only a shorter form than ]Varliaini^)\ to try and keep them distinct owing to the different colour of the periostracum is not correct, as the variety Warhaiiii. for example, may begin as straw-yellow and end as dark-brown. — For the sake of comparison I may give here the measurements of the few specimens from East Greenland : A. Montagu! var. striata: Length 21-5 19 17-5 Height T»y r nini 16 14-5 - Height Breadth Length Length 82.6 7„ 975 '""'• 45-3 7o 84.2 - 10.25 - 53-9 - 82.9 - 9 514 - Only one specimen (from Hekla Havn) is so short in form, that it can be referred to the typical Astartr Moiitagtii ; it has the following measttrements: Length Height Height Length Breadth Breadth Length 14 """. 12.75 """• 91-1 7o 775 ""'• 55-3 7'o This specimen also differs in its sculpture, the shell only showing fine lines of growth and not the usual concentric ribs. 2). Jan Mayen. None of the Danish Expeditions have found it here, but it is stated to have been taken by the Norwegian North-Atlantic Expedition as the variety globosa at a depth of 195 fm. (Friele) as also by the Austrian Expedition at a depth of 105 fm. (Becher). 9 The "Astartr Banksii Leach var. Warhami" of Posselt in his East Greenland Molluscs (I.e. 1895; PI. L f'gs- 3 -4) has to be referred in my opinion to the variety striata owing to the relative shortness of the shell. -) It is this specimen which is figured by Posselt, I.e., figs. 1—2, under the name of Astarte Banksii Leach. LAMELLIBRANCHIATA. lOI Iceland. A.Montagui has been taken in large quantity on the west coast, in part also on the east coast; from the south coast there are but few specimens and from the north coast onh- one, but whether this is due to imperfect collections or to the actual scarcity of the species on the north coast, I am unable to say'). The depths noted lie between ca. 8 — 50 fm. On the west coast it reaches to 19 """., and on the east coast to a very considerable size, namely 26.2 """. The various localities are as follows. East Iceland: Myre Bugt 26 fm. i val\e. Berufjordr, Djupivogr 6 — 9 - , mud with black sand. 50 spec. Mouth of Berufjordr 54 — 41 - , ooze. i — 64°58'N.L., i3°25'W.L 40 - 4—8: 27 valves. Breiddalsvik 14- 2 — &.i valve. Vattarnes 20 — 16 - i — Vidfjordr 8 — 12 - i — - 15 - 2 - Nordfjordr 40 - 9 — Seydis^ordr 15 — 20 - i — — , the mouth 38 — 14 - , mud. 12 — — , off Brimnes .... 40 - , ooze and clay. i — The specimens from East Iceland belong in part to the variety striata, in part to the t>pical form or to transitional stages between the two, as will be seen from the following measurements: Height Breadth LocaUtv Length Height Breadth 7- Length Length Djupivogr 26.2 ""^. 23 "'"■. 87.8 °/„ 12.5 "'"'. 47.7 % — 24.7 - 22.25- 90-1 - II-2 - 45-3 - — 22.5 - 18.75- 83.3 - 12 - 53.3 - Berufjordr 16 - 14.5 - 90.6 - 8 - 5° " Vattarnes 17 - H-S " 85.3 - 9.2 - 54.1 - Seydisfjordr 22 - 19.25 - 87.5 - 10 - 45 " 21.2 - 19 - 89.6 - 10.2 - 48.2 - — 20.5 - 18.5 - 90.2 - 10 - 48.8 - 20.2 - 17.8 - 88.1 - 10 - 49.5 - _. 20 - 18 - 90 - 10 - 50 - 20 - 17.2 - 86 - 10 - 50 — I9-.5 - 17 - 87.2 - 9.25 - 47.4 - — 19 - 17 - 89.5 - 9 - 47.4 - Nordfjordr 21.8 - 18.75- 86 - 10.8 - 49.5 - — 21.5 - 19 - 88.4 - 1 1.75 - 54.7 - — 20.2 - 18.25 - 90-3 - 9-5 - 47 - I) As Odhner in his list over the comparatively small collection of marine Mollusca from Iceland in the Stockholm Museum records the species from 2 localities from the north coast (Arkiv for Zoologi, Bd. 7, No. 4, 1910, p. 20), the first view- seems to be the most probable one. I02 LAMELUBRANCHIATA. Nortli Iceland: From here we have only a small specimen (12.5 "'"'. longi from Axafjordr 30 fm., sand and stones. i spec. But, in addition, Odhner (I.e.) records it from the following localities on the north coast, np to 18 """. in length : Raufarhofn 35 fm. 13 spec. Siglnfjordr 12 - Many spec. West Iceland: Skutilsfjordr. Dyrafjordr. Talknafjordr. N. W. of Talkni. Patreksfjordr 10—20 fm. — 14 - Grundarfjordr. — 12 - Hvalfjordr 24 - Faxafjordr 25 - — , month of KoUafjordr 91/2 - — — - — 9'/, — II - , fine black sand and ooze. — , off KoUafjordr 8 — ii'/z - , ooze and stones. — - — 10 - — , Keflavik 15 — 16 - , fine black .sand. — , 2 miles N.E. of Keflavik ig'/j — 20'/2 - , ooze. — , I mile E. N. E. of Helga- sker Vager 1 1 1/2 - — , 4.3 miles W. 3/^ S. of Hel- gasker Vager 25 - E. of Videy 9 — 10 - , fine sand and ooze. Reykjavik. — , beach. — (Engey) ?— 8V2 - , ooze. Hafnarfjordr 25 - , fine black sand and ooze. Skagi 21 - The maximum length is 19 "■'". 9 spec. I — 7 — I valve I spec. 3 — & 5 ' i'alves. I — 2 — 75 spec. & ca. 100 valv. 2 valves. I spec. cS: 40 valves. 10 — & ca. 100 valv. 3 — & - 225 — ca. 100 valves. 6 spec. & 135 valves. no valves. 1 spec. 2 spec. & 55 valves. 4 valves. 6 spec. & II valves. 20 valves. 2 spec. II valves. I valve. LAMEI.LIHRANCIIIATA. 103 K\- far the great uiajorit\- of ilu- West Icelandic specimens bcloni;;- to tlie typical A. Montagtti'^). Thus, all the specimens from the southern part of the west coast belong to the txpical form, as will be seen from the following examples: Height Breadth Locality Length Height S— Breadth Length Length Grundarfjordr 18.3 '""'. 17 ■""'. 92.9 "/^ 10 """. 54.6 ^i^ - 17 - 157 - 924 - 9 - 52-9 - Engey 17.2 - 15.8 - 91.9 - 8 - 46.5 - Hafnarfjordr 17.2 - 16 - 93 - 10 - 58.1 - — 16.5 - 15.8 - 95.8 - 10 - 60.6 - E. N. E. of Helganes 13.5 - 13 - 96.3 - 7.5 - 55.6 - Keflavik 14 - 13 - 92.9 - 7.5 - 53.6 - The typical A. Montagui also occurs on the northern part of the west coast, but by side of it we find moreover somewhat more elongated specimens, which approach to or may be entirely re- ferred to the variet\' striata: this is seen from the following measurements: Height , Breadth Locahtv Length Height Breadtli Length Length Talknafjordr 18.2 "'"'. 16 ">">. 87.9 "/^ 9 """. 49.4 % — 16.8 - 15.2 - 90.5 - 8.5 - 50.6 - — 15 - 14 - 93-3 - 8 - 53.3 - Patreksfjordr 19 - 16.5 - 86.8 - — 17 - 15-2 - 89.4 - 8.75 - 51.5 - 15-7 - 14 - 89.2 - 8 - 51 - — 14 - 13 - 92-8 - 7-5 - 53-6 - South Iceland: Vestmannaeyjar 30 fm., gravel. 5 valves. — 49 - , clay with a little mud. i spec. & 40 valves. 63°24' N. L., i7°5' W.L 70 - 2 valves. The maximum length of these specimens, which belong to the topical /{. Montagjii^ is 14""". Faeroes. Here the species is common at depths of ca. 5 — 50 fm. The maximum length is 19.8"'"'. The various localities are as follows: \'iderejde 10 fm. i spec. & 6 valves. Klaksvig 10—15 " i — & 7 — I) A specimen from Grundarfjordr is even so high and short, with the posterior margin sloping so steeply, that it resembles the form figured bv Brown under the name of Crassina obligua (lUustr. Conchol. Great Britain and Ireland, 1827, PL 18, fig. 6), but in the second edition of his work given as a variety of Crassina striata (lUustr. Rec. Conchol. Gr. Britain and Ireland, 1844, p. 96, PI. 38, fig. 6). Its inea.surements are a.s follows: height 17.5 '""'., length 17.5"!'"., breadth 10.5 mm. This characteristic form also occurs at the Kieroes. I04 LAMELLIBRANCHIATA. Klaksvig n fni-, from rhizoids of Laminaria. i spec. Rordovig 7 — lo - , black sand and small stones. 30 — & 14 valves. — 10 - , sand. 5 — & 4 — Fundingsfjord 12 — ca. 20 - , coarse sand and clay. 2 — & 2 — Andefjord 16 — 23 - 2—1 valve. Skaalefjord 4—5 - i valve. Kongshavn 2 spec. — 12 — 16 - , small stones, sand & ooze. 3 — & 14 valves. — ca. 50 - 33 — '^ 90 — Vestmansnnd - 70 - 12 valves. Vestmanhavn 3'/2 — 5 - , fine black sand. ca. 125 spec, (small). — 5 — 6 - , fine black sand. 10 spec. & 70 valves. vSorvaag 14 — 161/2 - , ooze. i valve. Midvaag, beach i — Thorshavn 3 — Nolso, deep hole at north end ca. 100 fm. i spec. & i valve. Vaagfjord 10 - i — 5 miles S. S. E. of Bispen 50 - 8 valves. 13 — W. by vS. of Munken - 150 - i valve. The Fjeroese specimens belong to the typical A. Aloiitagni. thongh sometimes with a tendency in the direction of \ds. striata, as will be seen from the measurements below: Height Breadth Locality Length Height ^^ — Breadth Length Length Klaksvig 20.6 "">'. 19.5 "'"'. 94.7 7o 9-8 """• 49 °/o Andefjord 19.8 - 17.5 - 88.4 - 10 - 50.5 - — 16.8 - 15.5 - 92.3 - 8.75 - 52.1 - Nolso 17.2 - 15.2 - 88.4 - 7.8 - 45.3 - Kongshavn 17 - 15.3 - 90 - 8.2 - 48.2 - — 16 - 14.2 - 88.8 - 8.2 - 51.3 - — 15-8 - 15 - 94-9 - 8.5 - 53.8 - — 15-5 - 13-8 - 89 - 8 - 51.6 - — 147 - 13 - 92-9 - 7-5 - 51 - — 14 - 13-5 - 964 - 8 - 57.1 - — 14 - 13 - 92-2 - 7-5 - 53-6 - Vaagfjord 14 - 12.7 - 90.7 - 7 - 50 - Fundingsfjord 12.8 - 11. 8 - 92.2 - 7-2 - 56.3 - Viderejde 13 - 11.7 - 90 - 7 - 53.8 - Concluding remarks. It may be seen from the foregoing, that there is a certain regularity in the variation of the species, since the form becomes elongated on the whole in the same degree as the marine climate becomes more severe. At the Faeroes and the southern West Iceland we have only the short A. Montagjti typico. though sometimes with a tendency in the direction of the slightly more elongated variety striata; at northern West Iceland the variety striata begins to appear LAMELUBRANCHIATA. 105 and at East Iceland it occurs conmionK tdj^'ether with tlie typical Montagui. At West Greenland the variety striata is by far the most predominant, and at the same time the still more elongated variety Warfiaiiii is appearing; lastly, at East Greenland the variety Warhnuii is almost the only form. Accompanying the elongation of the form we also find an increase in the ma.xiniuni length, namely from ca. 19 -20""". at the Fseroes and West Iceland to 23—26""". at East Iceland and Greenland. Distribution. Astarte Montagui is circnmpolar in arctic seas. Towards the sonth it reaches to the Aleutians and \'anconver Island in the Pacific, and in the .Vtlautic to Massachusetts and the Channel. Astarte sulcata da Costa. PI. IV, figs. 3 a— c. Pecfiiiicnliis snlcatus da Costa, Brit. Conchol., 1778, p. 192. — Astartr sulcata Forbes and Hanle\', Hist. Brit. Moll., I, 1853, p. 452, PI. 30, figs. 5- 6') & PI. 133, fig. 4; G. O. Sars, Moll. Reg. Arct. Norv., 1878, p. 52. Astarte sulcata Posselt (partim), Medd. om Gronland, XIX, 1895, p. 72; ibid. XXIII, 1898, p. 65. The "Ingolf" has taken this species at: St. 94. Off South-East Greenland 204 fm. W. of Iceland 250 - - - - 138 - 16. 98. 86 87 89 9 8. 85 84, 81 73 6. - - — (Brede Bugt) 76 - — — — no - - - — 310 - - — ■••■ 295 vS. W. of Iceland 136 4.1° C. I spec. 6.1° - I valve. 5.9° - 2 spec, and several hundred separate valves, mostly of very small specimen.s. I large valve and man)- quite small. ca. 20 valves. I spec. & I valve. 4 spec. & ca. 20 valves. 10 separated valves of young specimens. ca. 20 spec. & many valves. I valve. 6 ancient valves. I valve. Some fragments of larger val- ves and a number of valves, separate or connected, of quite small specimens. West Greenland. Posselt records A. sulcata from Igaliko Fjord, Sukkertoppen and the fjord off Upernivik; of these I have seen one specimen labelled as coming from the first-named locality, but in appearance it is so "European", that I think it not unlikely that some exchange of labels has taken place. ') In the explanation of the figures under the Plate, fig. 6 is given under the synonym A. Danmoniensis, fig. 5 by a type-error as A. triangularis. S. E. of Iceland 310 - 8.4° - 295 - 5.8° - 136 - 6.0° - 170 - 633 - 4.8= - 485 - 6.1° - 486 - 5-5° - 90 - 7.0° - The Ingolf-Expedition. II. 14 jq5 lamellibranchiata. East Greenland. Here there occurs a comparatively closeh" ribbed form of A. sulcata, which has been taken off the south-eastern ("warm") part by Nordenskj old's Expedition (1883) at 130 fm. depth and by the Ingolf-Expedition at St. 94 in 204 fm., as also by the Amdrup Expedition off Angraagssalik at a depth of 140 fm. The maximum length is 23 mm. — Further, INIobius'l records it from north-eastern Greenland, but I feel certain that this record is due to some mistake. [Jan May en |. Becher records the species from here-), but I am convinced that his record refers to a form of A. crenafa Gray (cf. A. crenata var. inflata, p. 117); A. sulcata is perfectly clearly, from the results of the lugolf-Expedition, a distinctl} warm-water form. Iceland. In addition to the stations mentioned of the Ingolf-Expedition, A. sulcata has later been taken at the following places: 63°i5' N. L., 22°23' W. L 170— 114 fm. 6 spec. S: 24 valves. 63°i8' - - 21'' 30' - - 94 - I — - I — 63°05' - - 20° 7' - - 293 - 15 valves. 62°57' - - i9°58' - - 500 - I valve. 63°2i' - - i7°3i' - - 69 - , black sand. i — 63°2i' - - I7°i5' - - 58 " 1 sand, stones, shell-gravel. 3 spec, and 12 valves. 63°24' - - 17° 5' - - 70 - , black sand with stones i spec, and 3 valves. and shells. Thus, taken on the \^\\o\&, A. sulcata may be said to be fairly common off western and southern Iceland ; living specimens have been taken at depths of 58 — 310 fm., but dead shells even at a depth of 633 fm. The maximum length is 26 ' , mm The Faeroes. From the investigations of recent years the Zoological Museum has obtained A. sulcata from the following places. Fundingsfjord 12—20 fm., coarse sand and clay. 9 spec. & 34 valves. Nolso, deep hole at north end ca. 100 - 4 — & 6 — 62°29' N. L,., 5''i7' W. L 160 - , stones and sand. i — & 5 — 62°29' - - 4''52' - - 112 - , sand. 2 spec. 62°i7'/2' - - 4°57' - - 144 - , clay and stones. 2 — 13 miles S. of Myggensesholm 70 - i spec. & 9 valves. S. W. of Myggenses 135 - 18 — S: 165 - 1) Die zweite Deutsche Nordpolarfabrt in d. Jahreu 1869 11. 1870. Wiss. Ergebn., 11, 1874, Zoologie, p. 251. 2) Die Osterr. Polarstation Jan Mayen, Beob.-Ergebn., Ill, iSS6, p. 71. LAMELLIBRANCHIATA. 107 6i°i5' N. L., 9°35' W. L ca. 475 fni. go valves. 61° 7' - - 9°3o' - - 440 - 12 spec. & 185 valves. 61° 9' - - 7°54' - - 181 - , sand and shells. 4 — & 2 — 6i''io' - - 5°46' - - 160 - , sand with stones and shell.s. 2 — ^ & i — 5 miles S. S. E. of Bispen 50 - i — 16 miles E. by S. of south point of Nolso ca. 80 - 2 — & 9 — 12 miles S. S. E. of Akralejte 150 - 70 — & 42 — 13 miles W. by S. of JMunken ca. 150 - 25 — y4. sulcata has thus been taken at various places round about and in part also at the Faeroes at depths of (12) 20—440 fni. It reaches a length up to 29 """. Remarks. Compared with other Astarte species, A. sulcafa is subject to comparatively little variation, so far as the present geographical region is concerned. The most important variation — so far as I can see — consists in a tendency of the number of ribs to increase somewhat in the western part of the geographical region of the species; in specimens from off the south-eastern Green- laud the ribs are so dense, that their number — in specimens of 19 — 23 "'"'. in length — amounts to ca. 35 — 42, whilst the number in t>pical specimens, 21 — 23""". in length, from the Faeroes is ca. 30—33. The form ma}' vary somewhat, as will be seen from the following measurements of some spe- cimens, most different from one another in regard to the three dimensions: Height , Breadth Locality Length Height Breadth — ^ 00 Length Length East Greenland 23 "■"'. 18.25™". 79-3 °/o 11.2""". 487% — — 20.25 - 15.5 - 76-5 - 9-5 - 46-9 - - - 20.25- 15-75 - 77-8 - 8.5 - 42 - Iceland 24 - 19.75 - 82.3 - 12.75 - 53-i - — 23.5 - 21 - 89.4 - 12 - 51.1 - Faeroes 26 - 21.5 - 82.7 - 13.5 - 5i-9 - — 23.5 - 17.75 - 75-5 - 12.5 - 53.2 - — 22 - 18.2 - 82.7 - 12 - 54.5 - As a further illustration of the change of form in this species as a whole, I may give here the measurements of 3 specimens, which I have dredged along with man}- others N. E. of Shetland, at a depth of 150- 220 fm. Height Breadth Length Height ^^^^ Breadth ^^^^ 26-™. 21.5 ■""'. 82.7% 12 ■■■■". 46.2% 25 - 19-5 - 78 - 11-75 - 47 - 25 - 21.75 - 87 - 13 - 52 - In illustration of the variabilit)- with regard to the number of concentric ribs, the following examples are represented on PI. IV: Fig. 3 a. A typical specimen from the Faeroes, Fig. 3 c. A specimen with comparatively closely-placed ribs, from East Greenland. 14* io8 LAMELUBRANCHIATA. Distribution. On the European side Astarte sidcata is distributed from the western part of the Mnrman Coast (Knipowitsch) to the Mediterranean and west coast of North Africa; it goes down into the Kattegat Over the Fferoes it reaches to the southern and western coasts of Iceland and to Denmark Strait off the south-eastern Greenland. The bathymetric distribution is 5 — ca. 1000 fm. Astarte elliptica Brown. PI. IV, figs. 4 a-g. } Venus coiiiprcssa Linne, Mantissa Plantarum Altera, 1771, Regni Animalis App., p. 546. — Crassina elliptica Brown, 111. Conchol. Great Britain and Ireland, 1827, PI- 18, fig. 3; 111. Rec. Con- chol. Great Brit, and Ireland, 1844, p. 96, PI. 38, fig. 3. — Astarte compressa Sars, Moll. Reg. Arct. Norv., 1878, p. 53')- Astarte semisnlcata Moller, Index Moll. Groenl., 1842, p. 19. — Astarte compressa Morch, Rink's Gronland, 1857, p. 91; Vidensk. Medd. Naturh. Foren. 1867, p. 95; ibid. 1868, p. 222; Arctic Manual, 1875, p. 131; Rink's Dan. Greenland, 1877, p. 441; Posselt, Medd. om Gronland, XIX, 1895, p. 72, PI. I, figs. 5—7 (var. dcpressa Poss.); ibid. XXIII, 1898, p. 66; Jensen, ibid., XXIX, 1909, p. 339. The "Ingolf" has taken this species at: St. 86. W. of Iceland 76 fm. 12 valves of young (mostly quite young) specimens. 87. - - — no - 5 valves of young .specimens. - 113. S. of Jan Mayen 1309 - 2 valves, - 104. N. W. of Iceland 957 - i valve of a young specimen. West Greenland. Here the species occurs commonly from the southernmost parts up to Melville Bay, on mud, clay, shell and stone ground. The depths noted for living .specimens lie between 10 and 235 fm.-). The ma.ximum length amounts to 36™"'. East Greenland. A. elliptica has been taken b\- Danish Expeditions at Angmagssalik, Cape Dalton, in Scoresby Sound and Forsblads Fjord, (3) 10— 30(50) fm., on mud, clay and stony ground, as also by the Germania Expedition at northern East Greenland (Mobius, as A. sulcata). The maximum length amounts to 30""". [Jan Mayen.] Here, curiously enough, the species has not been met with. Posselt (I.e. 1898, p. 67) records it from Jan Mayen and Copenhagen Museum as the authority or source, but this is due to some mis- take, as our Museum possesses no specimen of A. elliptica from this island. ') For the remaining synonyms cf. Kobelt: Prodr. Moll. Test. Mar. Europ. 188S, p. 392. =) A living, adult specimen from this considerable depth has been taken at 66°49' N. L., 56°28' W. L. LAMELLIBRANCHIATA. 109 Iceland. YiciQ Astarte cllipficci is common round the island; it occurs both on sand, ooze, mud and mixed bottom-soil; living it is taken at depths of 5— 6ofm., once of 100 fm. The maximum length is 38.5""". The various localities are as follows: East Iceland: Berufjordr, Djupivogr 6 — 9 fm., mud with black sand. — mouth 54 — 41 - , ooze. Faskrudstjordr 50 — 20 - , blue clay. 64°58'N.L., 13^25' W.L 40 - Eskifjordr o — 12 - \'idfj6rdr 15 - Nordfjordr 22 - — 40 - Seydisfjordr 9 — 5 - — , mouth 38 — 14 - , mud. — , mouth ca. 40 - , stomachs of haddock. — 50 — 20 - , blue clay. 65°42'N.L., i3°57'W.Iv 60 - Bakkafjordr 28 — 20 - , sand mixed with clay. — 32 — 25 - , sand mixed with clay. — 52—43 - , sand mixed with clay. The largest specimen is 38 "'™. long. North Iceland: Thistilfjordr 10—24 f™" sand and "coral". — 50 - ) clay with man\- stones. Axafjordr 22 - , mud. Skjalfandi Bugt 21 - , black sand. _ _ 31 " ) li^^ sand. 4 miles E. of Brik Skaer 100 - Husavik in E. 4 miles 42 - 66°i7'N. L., i8°i3'W. L 52 - 0fjord — just S. of Hrisey 18 - , clay. Veidileysa 21 — 25 - The largest of these specimens are 35 "'"'. long. 25 spec. 13 — I — & I valve. I — & 44 valves. 2 — 17 - 4 - 8 — & 6 \alves. I — 24 - I valve. 2 spec. I — 4 — and 2 valves. 22 — and 30 valves. 7 - and 5 valves. 2 spec. 30 valves. 14 spec. 5 — 19 — I — 4 — I valve. 40 spec. 5 — 7 — jIO IvAMELLIBRANCHIATA. West Iceland: Hesteyrarfjordr, at the head 15 — i7'/'2fm. i spec. «S: 30 valves. 0nundarfi6rdr 9 - 21 — Dyrafjordr, inside Thingnses 10 — 12V2 - , mud and small stones. 2 — & 40 valves. — 13 - 2 — Fossfjordr 44 - i — Talknafjordr 42 — N. W. of Talkni 2 - & 2 valves. Patreksfjordr 5- 5 — - 14 - I - Grundarfjordr i — Hvalfjordr 24 - 50 — & 70 valves. Faxafjordr 15 - 5 — — 25 - I valve. — , month of Kollafjordr .... 91/2 — 11 - , fine black sand and ooze. i spec, and 30 valves. — , off Kollafjordr 8 — 11 72 - , ooze and stones. 11 valves. — — — 10 - I spec. &: 10 valves. — , Keflavik i5. — 16 - , fine black sand. 3 — and 80 valves. — , ca. 2 miles N. E. of Kef- lavik 19V2— ao'/a - , ooze. 21 valves. , 1 mile E. N. E. of Helgasker Vager ii'/^ - 7 spec. , 4.3 miles W. 3/^ S. of Hel- gasker Vager 25 - 40 valves. Reykjavik (Engey) 7— S'/^ - 5 — — , roads 8- i spec. Hafnarfjordr 25 - , fine black sand and ooze. i — and 14 valves. The largest of these numerous specimens is 38.5 """. South Iceland: Vestmannaeyjar 30 fm., shell-gravel. 2 valves. — 49 - ) gray, fatty clay. 4 spec. & 4 valves. The largest specimen is 27 """. long. Faeroes, Here A. clliptica seems to be common at depths of 3 — 50 fm. The maximum length is 37 """. The separate localities at which the species has been taken are as follows: Viderejde 10 fm. 4 valves. Kvannesuud, between Videro and Bordo 4—6 - . i spec. LAMKM.IBRAN'CIIIATA. I II Klaksvis 6-10 fm. i spec. 10 — 15 - 40 — iSiniany valves. — II -, from Laininaria rliizoids. 18 — Arnefjord 0-15 - , hard ground. i — Bordovi.tj 7 — 10 - , black sand and small stones, i valve. — 10 - , sand with Laminaria. 4 spec. Andefjord 16—23 " 4 — Kongshavn 12—16 - , small stones, sand and ooze. 2 — — ca. 50 - ca. 25 spec. & 90 valves. Vestmanhavn S'A— 5 - > fi"«-' t)lack sand. 80 spec. — 5 — 6 - , fine black sand. 6 — & 40 valves. — 10 - I — — 10 — 30 - 3 valves. Sorvaag 14— 16' ^ - , ooze. i spec. & 2 valve.s. Nolso, beach i valve. Trangisvaag i'''4— 3 - i spec. & 2 valves. — 6 — 8 - I valve. Vaagfjord barely i - i spec. — 10 - I — S. W. of Myggen^s i35 - i valve ■). 1V2 — 2 miles off the month of Bordovig 20 — 30 - i spec. & i valve. Remarks. The material to hand from the Fseroes, Iceland and Greenland shows, that both the form and sculpture vary to a great degree in Astartc rlliptica. At the Faeroes, however, the character is fairly uniform, it seems. The species appears here with strongly marked folds right from the umbones down to the ventral margin and they only disappear at the very back. It is onl\' in a single specimen that the folds become indistinct a little below the middle of the sliell. The form is not specially variable, on the whole rather elongated, more or less compressed, sometimes however somewhat vaulted. Measurements of some of the specimens which differ in dimensions give the following result: Height Breaflth Length Height ^engih ^^'''^'"'^'^ Height 30 "'"'. 23 "'"'. 76.8% II "'">. 367% 31 - 23.5 - 75.8 - 12.5 - 40.3 - 31.25 - 22.5 - 72 - 14 - 44.8 - At Iceland, on the other hand, we very frequently find forms which lack the folds over a greater or smaller part of the shell; .sometimes the folds disappear below the middle of the shell, in other specimens the\- only reach to the middle of the shell, and some specimens even have folds only ■) The shell from this considerable depth has a ver\- ancient ("fossil") appearance. 112 LAMELLIBRANCHIATA. on the umbonal area. Such specimens may have great resemblance and are certainly often confused with the more or less folded varieties of Astarte borealis Chemn. ^^A. seiitisiilcafa Leach" etc.jM; the large ligament projecting over the shell of the last-named as also the more or less fibrous or frayed structure of the periostracum makes the separation in general quite easy. — The form also appears to be very variable, both in relative height and breadth, as will be seen from the following measurements. Height Breadth Locahtv Length Height Breadth Length Length Seydisfjordr 32.25 """'. 23.25 "'"\ 72.1 % q.5 "'"". 29.5 % - 31-25 - 21.75 - 69.6 - 12 - 38.3 - Nordfjordr 32.5 - 23.25 - 71.5 - 11.75 - 36.2 - Dyrafjordr 31 " 23 - 74.2 - 14 - 45-2 - Talknafjordr 32 - 25.5 - 79.7 - 14 - 43.8 - At West Greenland A. cUiptica is subject to similar variations as at Iceland. In regard to form there are specimens which are even higher and more vaulted than those which go to an extreme in this direction at Iceland, so that we find such dimensions as the following: Height Breadth Length Height ^ — Breadth Length Length 31.25"'". 26.25 "'"V 84% 15.2'""'. 48.6% 27-25 - 23.25 - 85 - 14.2 - 52.1 - It has obviously been sitch specimens as these, which have led Leche to set up the variety crassa^]. At East Greenland A. cUipfica usually appears with folds right down to the ventral margin; not rareh', however, they cease about the middle of the shell. — With regard to the form, this is remarkable on the whole for its elongation, as will be seen from the measurements below; Posselt for this reason set up a special variety d(prrssa (for specimens from Hekla Havn3). Height Breadth LocaUty Length Height Breadth Length Length Cape Daltou 29.5 """'. 21.5 "'"'. 72.9 % 12.5 "'"'. 42.4 % — — 29.5 - 21.5 - 72.9 - 11.5 - 39 - Hurry Inlet 27 - 20 - 74.1 - 9.5 - 35.2 - Hekla Havn 23.5 - 16 - 68.i - 8 - 34 - — — 22.5 - 16.5 - 73.3 - 7.75 - 34.4 - The following figures on PI. IV may serve as illustration of the varying form and sculpture in Astarte elliptica^ mentioned in the foregoing: Fig. 4 a and b represent a typical ^{. rlliptica (from the Faeroes), seen from the side and from above. ■) For example, both Morch and Posselt have made mistakes in this direction. 2) Leche: Ofversigt ofver de af svenska expeditionerna till Nowaja Semlja och Jenissej 1S75 oeh 1876 insamlade hafs-mollusker, p. 19, PI. I, figs. 3 a— b. Kongl. .Sv. Vet. Akad. Handl., Bd. 16, No. 2, 187S. 3) L. c. 1895, p. 72, PI. L figs. 5—7- r.AMRLURRANCHIATA. "3 Figs. 4 c and d represent a vcr\- elongated form (var. drprrssa Posse! ti, IVoni Hast (Treenland. Figs. 4e and f show a very high (and ventricose) form (var. crassa lycche), from West Greenland. ^i§'- 4& shows a specimen in which tlu- folds disappear almost about the middle of the shell. From West Greenland. Distribution. Astarte clliptica is an arctic-boreal sjjecies, known from the east coast of North America down to New England, from Greenland, Iceland, the Fseroes, British Isles, Danish waters down to Bornholm, Norway, north coast of Russia, Kara Sea and Spitsbergen. The batluinetric distribution is 3 — 235 fm. Astarte crenata Gray. PI. IV, fig.s. 5 a — m. Nicania crenata Gray, Parry's first voyage, Suppl. to Append., 1824, p. 242. Astarte crebricostata Morch, Rink's Gronland, 1857, p. 91; Vidensk. Medd. Naturh. Foren. 1S68, p. 222; Arctic Manual, 1875, p. 131; Rink's Dan. Greenland, 1877, p.441. — Asfartr crenata Posselt, Medd. om Gronland, XIX, 1895, p. 71 ; ibid., XXIII, 1898, p. 64; Jens|en, ibid., XXIX, 1909, p. 337. The "Ingolf has taken this species at various stations and in three varieties, namely: forma typica St. 29. Davis Strait. 68 fm. 0.2° C. I spec. St. 32 - 31 - 35 - 28. - 27, - I IS var. subcequilatcra Sowb. Davis Strait 318 fm. — — 88 - — — 362 - — — 420 - — — 393 - Jan Mayen 86 - 3-9° C. 1.6° - 3-6°- 3-5°- 3-8°- 0.1° - Numerous spec. 3 spec. Numerous spec. 6 spec, and a number of con- nected or separated valves. var. acuticostata Jeffr. St. 116. S. of Jan Mayen 37i fm. 15. N.W. of Iceland 330 - - 124. N. of Iceland 495 - - 126. - - — 293 - - 128. - - — 194 - - 106. E. of Iceland 447 - 3. Between Faeroes and Iceland. . . 272 - and also at the following station, where the variety cannot be determined: St 127. N. of Iceland 44 fm. 5.6° C. i spec. S: i valve (both .small). The Ingolf-Expedilion. II. S- — 0.4 ° c. Numerous spec. - 0.75° - I spec. — 0.6 ° - Numerous spec. -0.5°- I valve. 0.6 ° - 4 .spec. - 0.6 ° - 5 - 0.5° - 3 spec. & 4 valves. 15 114 LAMELLIBRANCHIATA. Astarte crenata is au extremely variable species and has given rise to not a few "species"; these I can only recognize as nominal, as my material contains transitions between them. The specimens living in the waters of Iceland, Jan Ma\en and Greenland mnst, therefore, in my opinion, be arranged under the following varieties: forma fypica^ var. snb(Tqnilatrra Sowb., var. crrbricosfata j\Ic. An dr. & Forb., var. iiiflafa Hagg and var. ncnficosfafa Jeffr. Forma typica. PI. I\', figs. 5 a, b and c. Asfarfr crenata Reeve, Conchol. Icon. XIX, 1874, Astart(\ sp. 9, PI. 2, fig. 9. — Astarte oblonga Sowerby, Thes. Couchyl. II, 1855, p. 781, PI. 167, fig. 19. — Astarte crenata Gray f. typica Jensen, Medd. om Gronland, XXIX, 1909, p. 337. The shell oval, more or less convex, with numerous (ca! 50), relatively low, concentric ribs, which disappear on the posterior part of the shell; periostracum light-coloured, yellowish. In its typical shape (PI. IV, figs. 5 a and b) it is quite characteristic, but this again is subject to great changes'). The ribs may be fewer and more prominent (PI. IV, fig. 5 c), so that the boundary towards var. s-ttlxrquilatera vanishes. All three dimensions are subject to considerable variation.s, as will be seen from the accompanying measurements: Height Breadth Locahtv Length Height Breadth Length Length Hurry Inlet 23 ""^. 17.5 ""^. 76.1 7„ 10.5 "^". 45.7 % Cape Hope 23.5 - 17.5 - 74.5 - 11.25- 47-9 - S. E. of Sabine Island 23.5 - 18.2 - 77.4 - 12.5 - 53.2 - — - — — 26.5 - 21.5 - 81.1 - 12 - 45.3 - This form occurs at East Greenland, where the Danish Expeditions 2) have taken it at the following places: Hurry Inlet 50 fm., cla>- with stones. Numerous spec. Cape Hope i2i - — — — 3 spec. Cape Tobin 120 - i spec. 72°24' N. L., i9°42' W. L 130 - i living & 2 empt\- spec. 72°5i' - - 20°23V2' W. L 124 - , clay. i spec, (empty). 72°53' - - 20^36' W. L 96 - 6 - 73°24' - - 20° - - 106 - 2 — S. E. of Sabine Island no - , fine clay with stones and gravel. 10 spec. &: some valves. and the Swedish Expedition of 1900 at the following places: 72°25' N. L., i7°56' W. I^ ca. 160 fm., stones and sand. 5 spec. 1) For some very .short and convex specimens Hagg has set up the varietv- incostata (Ark. f. Zoologi, Bd. 2, Nr. 2, I9°4. P- 37' PI- I. figs. II — 12); a similar form, Hkewise with weaklv developed and very densely placed ribs, is in onr Mii.seum from Unianak in West Greenland (cf. the following). 2) A. crenata has for the rest been taken at East Greenland (Shannon Isl., 30 fm.) already in 1869—70 by "Die zweite Deutsche Nordpolarfahrt" (cf. Wissenschaftl. Krgebnisse, II, 1S74, p. 252 under the name of Astarte crcbricostata). LAMELLIBRANCHIATA. I'5 74°35' N. L., iS^is' W. L 79fni., iiuid and stones. 2 sijec. Off Mackenzie Bay 58 - , imul. 10 — and the Belgica Expedition at tlie following places'): 75° 58-5' N. L., i4°o8' W. L 158 fni., bottom-temp. 0.4° C. 4 spec. 77°35-5' - - i8°i2' - - 28 - , - - - 1.79° - 16 - Thus, at East Greenland llie t\pical ^i. crciiafa has been taken at 13 localities from 70^36' N. E. — 77°35'-5 N. L., and at depths of 50 — 160 fm. The largest specimens are 28""". From West Greenland I have only seen it from the above-mentioned St. 29 of the "Ingolf and from Umanak, 250 fm., but I imagine that quite a number of the .specimens, which Posselt records in Consp. Faun. Groenl. simply as '■'•Astartr crciiafa", belong to the typical form. The specimens to hand from Umanak are remarkably short and on the whole much convex, as will be seen from the measurements below: Height Breadth LeuEtth Height ^ — Breadth - *■ " Length Length 21.5"'"-. 16.3™"'. 75-8% . ii.6""». 54 % 18.75 - 15-5 - 82.7 - 10.2 - 54.4 - 18 - 14.2 - 78.9 - 10.2 - 56.9 - 17.5 - 14 - 80 - 9 - 51.4 - 17 - 14 - 82.4 - 10.2 - 60 Var. subcequilatera Sowerby. PI. IV, figs. 5 d and e. Astartc stda-qiulatcra Sowerby, Thes. Conclul. II, 1855, p. 780, PI. 167, fig. 13; Reeve, Conchol. Icon. XIX, 1874, sp. 5, PL I, fig. 5. This resembles the typical crcuatn in the oval form of the shell, but the concentric ribs are fewer in number and coarser; the periostracum on the wliole darker, \ellowish-brown, oHve-coloured or brown. The form is besides subject to great variation, as will appear clearly from the measurements below; it varies from the elongated-oval or elliptical to the orbicular, somewhat triangular: Height , , Breadth Locality Length Height ^^^- Breadth ^-^-- Ingolf St. 27 27 """. 21.5 "■"". 79-6 % 13-5 '""'• 5° % - - 26.5 - 19-5 - 73-6 - "-5 - 434 - — - 32 24.5 - 18.25 - 74-5 - IO-75 - 43-9 - Julianehaab 24.5 - 21.5 - 87.8 - i4-3 - 584 - Jan Mayen 3° - 22 - 73-3 " H " 46-7 - _ _ 27.75 - 21.75 - 784 - 14-5 - 52-3 - ■) Grieg, in Due d'Orleans: Croisiere occanographique, 1909, 13.534. 15* jj5 lamellibranchiata. The ribbing ma>' also be subject to some variation, in regard to denseness and strength. This variety is common at West Greenland; apart from the "Ingolf stations mentioned before I have seen specimens from the following localities: Julianehaab. Month of AmeraHk Fjord (as a short, convex, rather denseh* ribbed form). 66°49' ^- L., 56°28' W. L 235 fm., sand and ooze. 4.4° C. Disko Bay 65 - Quite a number of the localities which Posselt notes from West Greenland under Astartc crcnafa Gray (Medd. om Gronland, XXIII, 1898, p. 64), also refer probably to the \m&ty siib(rtjuilaf', 250 — 790 fm. ("Thor", 1906), x 3. c. A part of the shell showing the radiating ribs, x 20. — 8. Lima subovata Jeffreys. a & b. A specimen from Davis vStrait, 1435 fm. (Ingolf St. 36). x 4. c. A part of the shell showing the numerous radiating ribs, x 20. — 9. Lima ingolfiaiia n. sp. a. A right valve from W. of Iceland, 568 fm. (Ingolf vSt. 90). x 4. b. A left valve from S. W. of Iceland, 799 fm. (Ingolf St. 78). x 4. c. The dorsal margin of the shell seen from the inner side, x ca. 18. d. A part of the shell showing its finely scaled or spined radiating ribs, x 30. — 10. Lii)ia Jeffrey si Fischer. a. A left valve from S. of Iceland, 500 fm. ("Thor", 1903). x 2. b. A right valve from S. of Iceland, 293 fm. ("Thor", 1903). x 2. c. A part of the shell showing its squamular, radiating ribs, x 12. — II. Lima sarsii Loven. a & b. A right and a left valve, from Norway (Bergen), x 5&.4. c. The upper part of the shell seen from tlie inner side, to show the crenulated cardinal margin, x 30. d. A part of the shell showing its densely and coarsely scaled surface, x 30. The Ingolf Expedition, II, 3. Ad. S. Jensen: Ln>i/rllihranckiata, PL II. i 1 a ig „# 1 b 2 b 1 c > ; // ^ -> 5 a ^ ■P| if 3 b f 3 c 1 i I /> 11 e Pacht (C- Crone phototyp. Plate III. Plate III. Fig. T. Modiola iiiodiolus L., young. a. A left valve from the inner side, x J/'- Iceland. b. The anterior end of the same valve, x 7. — 2. Modiola pliaseolina P h i 1 i p p i. a. A left valve from the inner side, x i. Iceland. b. The anterior end of the same valve, x 8. — 3. Idas argent ens Jeffreys. a. A left valve from the outer side, x 672- S. of Iceland, 975 fni. (Ingolf St. 67). b. A left valve from the outer side, without the hairy periostracum. x 12. c. A specimen from the upper side, x 12. d. Hinge of right valve, x 10. e. Hinge of the same, x 20. — 4. Modiola ria discors L. var. Iccvigafa Gra\\ a. A specimen from Spitzbergen. x i. b. Dorsal view of the same, x i. — 5. Modiolaria discors L,. var. snbstriaia Gray. a. A specimen from West Greenland, x i. b. Dorsal view of the same, x i. c. A 25art of the middle area to show its "smooth" (simply striated) surface, x 5. — 6. Adodiolaria discors L. a. A specimen from Denmark, x 2. b. Dorsal view of the same, x 2. — 7. Modiolaria corrugata St imp son. a. A specimen from Spitzbergen. x I'/j. b. A specimen from West Greenland (Fiskenaesset). x 172- c. Dorsal view of the same, x 172. d. A part of the middle area to show its shagreen-like wrinkled surface, x 5. — 8. Modiolaria faba (M filler) Fabricius. a. A specimen from West Greenland (Ritenbeuk). x i. b. Dorsal view of the same, x i. c. Interior of the right valve, x i. — 9. Cardiiivi fasciatum Montagu. a & b. A specimen of the short, strongly ventricose form, x i^/.. Faeroes, 20 — 30 fm. c & d. A specimen of the somewhat elongated, not much tumid form, x 3. West Iceland (0nundarfj6rdr), ca. 12 fm. e. A specimen with tubercles not only on the anterior and posterior area, but also on the middle area, x 6. West Iceland ((jnundarfjordr), ca. 12 fm. f. That form which was confused by Morch with C. cdnlc L,. x 1-/3. Faeroes. g. The same half from in front, x 3. h. The same half from behind, x 3. i. A specimen with an obliquely cordiform contour, x S'/j. Faeroes, 135 fm. k. A specimen half from behind showing an intercostal sculpture in the form of a fine pricking, x 5. West Iceland (Onundarfjordr), ca. 12 fm. — 10. Cardium ciliahiiii Fabricius. A very young specimen, x 1072- East Iceland (Bakkafjordr), 52 — 43 fm. — II. Cardium echinatum L. A very young specimen, x 1072. South Iceland, 17 — 23 fm. — 12. Cardium (Scrripcs) groeulandicum Chemnitz. a. A very young, strongly sculptured specimen, x 6. West Greenland (Godthaabs Fjord). b. A very young, comparatively smooth specimen, x 5. West Iceland (Onundarfjordr), 10 fm. The Ingolf Expedition, II, 5. Ad. S. Jensen: LamcUibranchiata, PL III. 3 a 1 a 4 a 3 d 3 e 'W9»zi^a»^^ jf ^^%i^ 3 b 2 a *. ^ 6 a 9 a 9 b r 8 a S b ^^ 8 e 7 d 9 c 9 I: 9 e mim U -■ : ' \V 10 E. Bang del. .^ // 9 d 9 I, 9 f . * 9 i 12 a ,!l a 9 '^JJI 12 b I'acht S Crone pliototyp. Plate IV. Plate IV. Fig. I. Astartr boreal is Chemnitz. a. A siiecinien without folds and with an almost smooth periostracum. x i. West Iceland, 22 fm. b. The same from above. c. A very high form, with quite narrow folds on the uppermost part of the shell and with fairly thick, fibrous periostracum on the lowest part, x i. West Iceland (Faxafjordr), 8— 11V2 fm. d & e. A strongly compressed form with distinct folds on the uppermost part of the shell. X I. West Greenland. f. A very elongated form from East Greenland (Hekla Havn). x I'/a- — 2. Astartc Mo7itagui T)\\\\^ yYL. a. Forma fypica, a short and high, somewhat triangular form, x 172- West Iceland (Faxa- fjordr), 15 — 16 fm. b. Van striata (Leach) ,Sars, a more elongated form, x i'/,. West Greenland (Jakobshavn). c. Var. Warliaiiii Hancock, an elongated, elliptical form, x i. East Greenland (Hurr\- Inlet), 10 fm. — 3. Astarte sulcata da Costa. a & b. A typical specimen from the Faeroes, 150 fm. x i. c. A specimen with comiDaratively close-placed ribs, from Denmark Strait off south-eastern Greenland (Ingolf St. 94), 204 fm. x i. — 4. Astarte clliptica Brown. a & b. A typical specimen from the Fceroes (Klaksvig), 10 — 15 fm. x i. c & d. A very elongated form, from East Greenland (Hekla Havn). x i. e & f. A very high and convex form, from West Greenland, x i. g. A specimen in which the folds disappear almost about the middle of the shell, x i. West Greenland (Vaigat). — 5. Astarte creiiata Gray. a & b. A typical specimen from East Greenland (Hurr>' Inlet), 50 fm. x i. c. A specimen with fewer and more prominent ribs, x i. East Greenland (Cape Hope), 121 fm. d & e. A specimen of var. siibwquilatera Sowerby. xi. Davis Strait (Ingolf St. 32), 318 fm. f & g. A specimen of var. crebricostata Mc. Andr. & Forbes, x i. North Iceland (Skage- strands Bugt), 119 fm. h & i. A specimen of var. ii/ftafa Hagg. x i'/^. East Greenland (Forsblads Fjord), 90 — 50 fm. k & 1. A specimen of var. aciiticostata Jeffreys, x I'/'a- S. of Jan Mayen (Ingolf >St. 116), 371 fm. m. A part of the shell, more magnified. The Ingolf Expedition, II, 5. Ad. S. Jensen: Lamellibranchiata , PI. IV 1 a 1 d 2 e 4 e 3 b 1 b S ft 4 d If 4 c # 4 f ^ 4 a -^^ I 49 a a E. Bang et Th. Block del. 5 b ■J 9 .j It y 6 I J (/ /;- o 1; Paclii (t Crone phototyp. THE INGOLF-EXPEDITION 1895 — 1896. THE LOCALITIES, DEPTHS, AND BOTTOMTEMPERATURES OF THE STATIONS. Depth Depth Depth Station Nr. Lat. N. Long.W. in Danish Bottoni- tenip. Station Nr. Lat. N Long.W. in Danish Bottom- temp. Station Nr. Lat. N. Long. W. in Danish Bottom- temp. fathoms fathoms fathoms I 62° 30' 8°2I' 132 7°2 24 63° 06 56° 00' 1 199 2°4 45 61° 32' 9° 43' 643 4°i7 2 63° 04' 9° 22' 262 5°o 25 63° 30 54° 25' 582 3°3 46 61° 32' 11° 36' 720 2°40 3 63° 35' 10° 24' 272 o"5 63° 51 53° 03' 136 47 61° 32' 13° 40' 950 3°23 4 64° 07' 11° 12' 237 2°5 26 63° 57 52° 41' 34 o°6 48 61° 32' 15° II' 1150 3°i7 5 64° 40' 12° 09' 155 64° 37 54° 24' 109 49 62° 07' 15° 07' 1120 2°9I 6 63° 43' 14° 34' 90 7°o 27 64° 54 55° 10' 393 3°8 50 62° 43' 15° 07' 1020 3°i3 7 63= 13' 15° 41' 600 4°5 28 65° 14 55° 42' 420 3°5 51 64° 15' 14° 22' 68 7°32 8 63° 56' 24° 40' 136 6°o 29 65° 34 54° 31' 68 0°2 52 63° 57' 13° 32' 420 7°87 9 64° 18' 27° 00' 295 5°8 30 66° 50 54° 28' 22 i°o5 53 63° 15' 15° 07' 795 3°o8 lO 64° 24' 28° 50' 7S8 3°5 3' 66° 35 55° 54' 88 i°6 54 63° 08' 15° 40' 691 3°9 11 64° 34' 31° 12' 1300 i°6 32 66° 35 56° 38' 31S 3°9 55 63° 33' 15° 02' 316 5°9 12 64° 38' 32° 37' 1040 o°3 33 67° 57 55° 30' 35 o°8 56 64° 00' 15° 09' 68 7°57 13 64° 47' 34° 33' 622 3°o 34 65° 17 54° 17' 55 57 63° 3/ 13° 02' 350 3°4 14 64° 45' 35° 05' 176 4°4 35 65° 16 55° 05' 362 3°6 58 64° 25' 12° 09' 211 o°S 15 66° 18' 25° 59' 330 -o°75 36 61° 50 56° 21' 1435 i°5 59 65° oo' 11° 16' 310 -o°i i6 65° 43' 26° 58' 250 6° I 37 60° 17 54° 05' 1715 i°4 60 65° 09' 12° 27' 124 QOg 17 62° 49' 26° 55' 745 3°4 38 • 59° 12 51° 05' 1870 i°3 61 65° 03' 13° 06' 55 o°4 1 8 61° 44' 30° 29' "35 3°o 39 62° 00 22° 38' 865 2°9 62 63° 18' 19° 12' 72 7°92 19 60° 29' 34° 14' 1566 2°4 40 62° 00 1 21° 36' 845 3°3 63 62° 40' 19° 05' 800 4°o 20 58° 20' 40° 48' 1695 i°5 41 61° 39 17° 10 1245 2°0 64 62° 06' 19° 00' 1041 3°i 21 58° 01' 44° 45' 1330 2°4 42 6i°4i 10° 17' 625 o°4 65 61° 33' 19° 00' 1089 3°o 22 58° 10' 48° 25' 1845 i°4 43 6i°42 10° 11' 645 o°o5 66 61° 33' 20° 43' 1128 3°3 23 60° 43' 56° 00' Only the Plankton-Net nsed 44 6i°42 9° 36' 1 545 4°8 67 61° so- 22° 30' 975 3°o Station Nr. ' Lat. N. Long. W. Depth in Danish fathoms Bottom- temp. Station Nr. Lat. N. Long.W. Depth in Danish fathoms Bottom- temp. Station Nr. Lat. N. Long. W. Depth in Danish fathoms Bottom- temp. 68 62° 06' 22° 30' 843 3°4 92 64° 44' 32° 52' 976 i°4 iiS 68° 27' 8° 20' 1060 — i°o 69 62° 40' 22° 17' 5S9 3°9 93 64° 24' 35° 14' 767 i°46 119 67° 53' 10° 19' lOIO — i°o 70 63° 09' 22° 05' 134 7°o 94 64° 56' 36° 19' 204 4° I 120 67° 29- 11° 32' 885 ~i°o 71 63° 46' 22° 03' 46 65° 31' 30° 45' 213 121 66° 59' 13° II' 529 -o°7 72 63° 12' 23° 04' 197 5°7 95 65° 14' 30° 39' 752 2°I 122 66° 42' 14° 44' 115 i°S 73 62° 58' 23° 28' 486 5°5 96 65° 24' 29° 00' 735 I°2 123 66° 52' 15° 40' 145 2°0 74 62° 17' 24° 36' 695 4°2 97 65° 28' 27° 39' 450 5°5 124 67° 40' 15° 40' 495 -o°6 6i°57' 25° 35' 761 98 65° 38' 26° 27' 1 38 5°9 125 68° 08' 16° 02' 729 — o°8 61° 28' 25'> 06' 829 99 66° 13' 25° 53' 187 6°i 126 67° 19' 15° 52' 293 -o°5 75 6r°28' 26° 25' 780 4°3 100 66° 23' 14° 02' 59 o°4 127 66° 33' 20° 05' 44 5°6 76 6o'= 50' 26° 50' 806 4°i lOI 66° 23' 12° 05' 537 -o°7 128 66° 50' 20° 02' 194 o°6 77 60° 10' 26- 59' 951 3^6 102 66° 23' 10° 26' 750 -o°9 129 66° 35' 23° 47' 117 6°5 78 60° 3/ 27° 52' 799 4°5 103 66° 23' 8° 52' 579 -o°6 130 63° oo' 20° 40' 338 6°55 79 60° 52' 28° 58' 653 4°4 104 66° 23' 7° 25' 957 — i°i 131 63° go' 19° 09' 698 4°7 So 61° 02' 29° 32' 935 4°o 105 65° 34' 7°3i' 762 — o°8 132 63° oo' 17° 04' 747 4°6 81 61° 44' 27° 00' 485 6°i 106 65° 34' 8° 54' 447 -0=6 133 63° 14' 11° 24' 230 2°2 82 61° 55' 27° 28' 824 4° I 65° 29' 8° 40' 466 134 62° 34' 10° 26' 299 4°i 83 62° 25' 28° 30' 9J2 3°5 107 65° 33' 10° 28' 492 -o°3 135 62° 48' 9° 48' 270 o°4 62° 36' 26° Ol' 472 108 65° 30' 12° 00' 97 i°i 136 63° 01' 9°ii- 256 4°S 62° 36' 25° 30' 401 109 65° 29' 13° 25' 38 I "5 137 63° 14' 8° 31' 297 -o°6 84 62° 58' 25° 24' 633 4°S 110 66° 44' 11° 33' 781 -o°8 138 63° 26' 7° 56' 471 -o°6 85 63° 21' 25° 21' 170 III 67° 14' 8° 48' 860 — o°9 '39 63'' 36' 7° 30' 702 -o°6 86 65° 03'& 23° 47V. 76 112 67° 57' 6° 44' 1267 -i°i 140 63° 29' 6° 57' 780 -o°9 87 65° 02', 23° 56'. no "3 69° 31' 7-^ 06' 1309 -i°o 141 63° 22' 6° 58' 679 -o°6 88 . 64° 58' 24° 25' 76 6=9 114 70° 36' 7° 29' 773 — i°o 142 63° 07' 7° 05' 587 -o°6 89 64° 45' 27° 20' 310 8<=4 115 70° 50' 8°29' 86 o°i 143 62° 58' 7° 09' 388 -o°4 90 64° 45' 29° 06' 568 4°4 116 70° 05' 8° 26' 371 -o°4 144 62° 49' 7= 12' 276 i°6 91 64° 44' 31° 00' 1236 3°i 117 69° 13' 8° 23' 1003 — i°o -••c^ii^" THE DANISH INGOLF-EXPEDITION. HITHERTO PUBLISHED: 1899. Vol, I, Part I. I. Report of the Voyage by C. F. Wan del (i plate) 1 2. Hydrography by Martin Knudsoi (34 plates) j igoo. . — Part II. .3. The deposits of the sea-bottom by O. B. Bocggild * (7 charts) 4. Current-bottles by C. F. JVandel (i plate) 1899. Vol- II' Part I. The ichthyological results by C/tr. Liitkcn (4 plates) . . . 1899. — Part II. On the Appendices genitales (Claspers) in the Greeuland- Shark, Somniosus microcephalus (Bl. Schn.), and other Sela- chians by Hector F. E.Jnngcrseu (6 plates) 1900. — Part III. Nudibranchiate Gasteropoda by R. Bergh (5 plates)... 1904. — Part IV. The North-European and Greenland Lycodinse by Adolf Severin Jensen (10 plates) . . , 1912. — Part V. Lamellibranchiata, Parti by Ad. S. Jensen. (4 plates and 5 figures in the text) 1899. Vol. Ill, Part I. Pycnogonidse by Fr. Mei)icrt (5 plates) 1908. — Part II. Crustacea Malacostraca, I: Decapoda, Euphausiacea, Mysidacea by H. J. Hansen (5 plates) 1903. Vol. IV, Part I. Echinoidea, Part I, by T//. Morfensen (21 plates) 1907. — Part II. Echinoidea, Part II, by 77/. Morfensen (19 plates) 1904. Vol. V, Part I. Pennatulida by Hector F. E.Jtmgersen (3 plates) 1912. — Part II. Ctenophora by T/i. Mortensen (10 plates and 15 figures in the text) 191 2. — Part III. Ceriantharia by Oskar Carlgren (5 plates and 16 figures in the text) 1902. Vol, VI, Part I. Porifera (Part i), Homorrhaphidte and Hetero'rrhaphidse by Will. Lundbeck (19 plates) 1905. — Part II. Porifera (Part 2), Desmacidonidse (Pars) by Will. Lundbeck (20 plates) 1910. — Part III. Porifera (Part 3), Desmacidonidae (Pars) by Will. Lundbeck (II plates) Kr. 25,00 (Sh. 30) 8,00 ( - 11) 13,00 { - 18) 4,75 ( - 7) 9,75 ( - 13) 8,00 ( - II) 6,00 ( - 9) 8,00 ( - II) 20,00 ( - 24) 19,00 ( - 23) 6,50 ( - 9) 10,50 ( - 14) 6,00 ( - 9) 17,00 ( - 22) 20,50 ( - 25) 12,00 ( - 16) / ■ v'<- *