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important determining factor, for no other species of Stegodon described by Lydekker or Falconer is known to have tusks of greater length than 7 feet. This fact, coupled with the observations, though imperfect, of the cranial structures mentioned before, inclines me to ascribe the fossil to an adult male of S. ganesa, Falconer and Cautley.
The stratigraphic position of the fossil is interesting. As stated above the lithological characters of the beds Stratigraphic position. in which it occurs furnish no certain guide. as to the stratigraphical position of the remains and in the absence of other determinable fossils, or of detailed stratigraphic mapping of this area, it is impossible to give the exact horizon of these beds beyond stating that they are removed from the top of the boulder-conglomerate zone by no less than 10,000 feet of intervening strata and are in close proximity to the sand-rock division of the middle Siwalik. In view, however, of the fact that according to the more detailed and careful zoning by Dr. Pilgrim of the upper and middle Siwalik stages of the Salt-Range and the Siwalik hills areas, the lowest horizon of Stegodon ganesa may be taken as near the base of the Pinjor zone, we are constrained to the conclusion that either this species of Stegodon appeared at an earlier horizon than that in which it has hitherto been found or that the upper Siwalik stage of the Jammu hills has locally attained the unusual thickness of more than 10.000 feet. Perhaps both inferences are in part true and it is possible that the present species should be ascribed to the Tatrot horizon.
ON A COLLECTION OF LAND AND FRESHWATER FOSSIL MOLLUSCS FROM THE KAREWAS OF KASHMIR. (With Plate 29.) BY B. PRASHAD, D.Sc., Officiating Director Zoological Survey of India.
IN describing the lacustrine Karewa deposits of Kashmir in 1859 Gedwin-Austen1 stated that "In all my wanderings amongst the Karewah-Hills, I never was able to find the slightest trace of a land or freshwater shell in any of the many sections I have examined." Later 2 some molluscs from similar deposits in Kashmir collected by Godwin-Austen were listed by Woodward as being from Kuardo, but none of the species were found as fossils and, with the exception of G. pankongensis (Nevill) v. Martens, none of them are represented in Dr. Wright's collections which form the subject of this paper. In 1912 Middlemiss3 found apparently near the same locality where Dr. Wright's fossils were collected, several examples of Planorbis and some unrecognisable fragments of shells. So far as I have been able to trace, no other fossil or subfossil molluscs, whether land or freshwater, have been recorded from the Karewas of Kashmir.
The land and freshwater fossil molluscs described in this paper were collected by Dr. Wm. J. Wright in 1920 in the area lying south of Lat. 34° 10'. All the fossils described below are from a group which Dr. Wright characterised as K-9 in his notes. This bed according to him is approximately 365 feet thick and consists of
chiefly fine buff weathering sandstone and shale," including "beds of dark shale and sandstone near the top." In one section the group contains considerable dark shale and just below Guravet Khurd there are thin seams of lignite."
The collection is not a large one, in that only five speciesthree Gastropods and two Pelecypods-are represented, but is very interesting owing to the first find of a Unionid, whether living or fossil, in the Kashmir territory.
1 Godwin-Austen, Quart. Journ. Geol. Soc. London, XV, p. 225 (1859).
? Woodward, Quart. Journ. Geol. Soc. London, XX, p. 388 (1864). Middlemiss, Rec. Geol. Surv., Ind., XLI, p. 121 (1912).
I have been able to recognize the following species:
I am indebted to Dr. E. H. Pascoe, Director, Geological Survey of India, for giving me the opportunity of working out this interesting collection. My thanks are also due to Mr. H. C. Jones, Superintendent, Geological Survey of India, for valuable help in looking up the literature on the subject.
Genus BENSONIA Pfeiffer.
(Plate 29, fig. 1.)
1855. Bensonia, Pfeiffer, Malakozool. Blatt. p. 119.
1908. Bensonia, Blanford & Godwin-Austen, Faun. Brit. Ind. Mollusca (Testacellidae & Zonitidae), p. 171.
Dr. Wright collected two specimens of a Zonitid from the north bank of the Kakriaj Nar. Some remains of similar shells were also found in a bed in Square C-2 of Survey of India sheet 43. Unfortunately both the shells are badly broken, and in none of the two the mouth is preserved. The form and sculpture, however, suggest that the fossils probably belong to a species of Bensonia nearly allied to B. monticola (Hutton).
Genus BITHYNIA Leach.
1818. Bithynia, Leach in Abel's Narrative of Journey into Interior of China, p. 362.
This genus of the family Hydrobiidae or Paludestrinidae is represented in the Kashmir collections by a variety of the
widely distributed species Bithynia tentaculata (Linn.). This species is common all over Central Europe 1 from Portugal to Amur; in North Europe occurring as high up as St. Petersburg and North Norway; England and Ireland and extending into North America to Canada through Greenland. In North Africa it is said to occur in Algeria and Morocco, and in Asia it has definitely been recorded from Western Siberia, Kashmir and quite recently from Punjab in the Salt Range.2 The variety from Kashmir and the Salt Range is the one described below as the var. kashmirensis Nevill.
As a fossil the species is known from various places in Germany (Kreglinger loc. cit. p. 310) and in England it has been found from the Pliocene through Pleistocene to Holocene periods.3
BITHYNIA TENTACULATA (Linn.) var. KASHMIRENSIS Nevill.
(Plate 29, figs. 2-5.)
1885. Bithynia tentaculata var. kashmirensis, Nevill, Hand-List Moll. Ind. Mus., II, p. 39.
Nevill only gave the name kashmirensis and the measurements of a specimen of his new variety to specimens from Kashmir (exact locality not stated) and Srinagar. As the variety has never been figured or described, I include here a few notes on its diagnostic characters, and figure the type-shells. The fossils collected by Dr. Wright are quite identical with the type series of Nevill and the specimens collected by me near Srinagar in 1921.
The variety kashmirensis differs from the typical form in having all the whorls more tumid, the penultimate and body-whorl being specially marked in this respect; the suture more deeply impressed ; the shells slightly more umbilicate; the mouth opening more regularly rounded anteriorly and the shell somewhat thicker.
The fossils of this species were collected from the same locality in which Bensonia sp., described above, was found.
1 See Kobelt, Rossmassler's Icon. Land und Süssw. Moll. (n. f.) V, p. 63 (1892) and Kreglinger, Syst. Verzeich. Deutschland Binnen-Moll., p. 309 (1870).
2 Annandale & Rao, Rec. Ind. Mus., XXV, p. 601 (1923).
3 Kennard, Proc. Malacol. Soc., London, XVI, p. 97 (1924)
Genus GYRAULUS Agassiz.
(Nevill) v. Martens.
(Plate 29, figs. 6, 7.)
1922. Planorbis (Gyraulus) pankongensis, Germain, Rec. Ind. Mus., XXI, p. 110.
In Dr. Wright's collection there are a number of Planorbids collected with the specimens of B. tentaculata var. Kashmirensis referred to above. I have no hesitation in referring these to Nevill's species pankongensis which was described from Pankong Lake. Specimens of this species from the Kashmir valley are also in the Indian Museum collection.
Weber1 wrongly considers this to be only a form of G. glaber (Jeffr.), as the species is not allied to G. glaber, but is, as Nevill rightly pointed out, allied to G. convexiusculus (Hutton).
I have little doubt that the records of P. nanus by Woodward3 and of Planorbis (Gyraulus) albus var. and Planorbis (Armiger) nanus by Godwin Austen1 all refer to this species.
Genus CORBICULA Meg. von Mühlfeldt.
(Plate 29, fig. 8.)
In the collection there are both the valves of a shell of a species of Corbicula collected from near the spring at Gogajipathar. Unfortunately the shells are incomplete and badly compressed, and the hinge is not visible. It is, therefore, not possible to identify the
Weber, Zool. Jahrb. (Syst.), XXIX, p. 307 (1910).
Nevill, Scientific Results, Second Yarkand Mission, Mollusca, p. 10 (1878).
3 Woodward, Proc. Zool. Soc., London, p. 186 (1856) and Proc. Geol. Soc., London, XX, p. 388 (1864).
4 God win-Austen, Proc. Malacol. Soc., London, III, pp. 260, 261 (1899).