162 Records of the Indian Museum. [Vol. XV, 



GASTROPODA. 



Order PECTINIBRANCHIATA. 

 Family NERITIDAE. 



Genus Neritina, Montfort. 



Three species of this genus have been described from Mesopotamia 

 and I have here to put on record the occurrence of a fourth hitherto 

 known from Palestine. The four species are easily distinguislied. They 

 are N. mesopotmnica, Mousson, N. cincteUa, Martens, N. euphratica, 

 Mousson and A', jordani, Sowerby. The first two are only known 

 from upper Mesopotamia, but although N. euphratica is stated to be 

 widely distributed through the whole country, none of the specimens I 

 have examined can be assigned to it. 



The four species may be distinguished as follows : — 



1. Shell witii an obtuse ridge on the body-wliovl N. cincteUa. 



II. Shell with a broad, shallow constriction running round 

 the main whorl, distinctly taller than broad, marked 

 with dark and pale zig-zag lines ; the inner lip without 

 denticulation or emargination ... ... N. jordditi. 



III. Shell without transverse constriction or ridge — 



A. Shell slightly taller than wide, of a uniform 



blackish colour ; inner lip entire ... N. incsopotamlcu. 



B. Shell wider than tall, marked with dark and 



pale zig-zag lines, with a slight emargination 



in the middle of the inner lip ... ... N. cuiihratica. 



Neritina jordani, vSowerby. 



1899. Neritinn jordani, Kobelt in Rossmiissler's Icon. Land-ii. Sussiv. Moll. (n. f.) 



VIII, p. 2, pi. ccxi, fig. 1319. 

 1899. Neritina jordani var. turris, id., ibid., p. 3, pi. ccxi, fig. 1320. 



There are numerous shells of this species in collections from the bank 

 of the Euphrates at Nasariyeh and from both lacustrine and paludine 

 deposits in the same neighbourhood. They agree very closely, except 

 in being rather smaller, with shells of the var. turris of Mousson collected 

 by myself in the Lake of Tiberias. All are variegated, but there is con- 

 siderable variation in the relative breadth of the dark and the pale 

 zig-zag markings. 



Family HYDROBIIDAE. 



Bithynia badiella, Parreyss. 



1874. Bithynia badiella, IMousson, .Jowrn. de Conch. XXI, p. 45. 



Shells are abundant in lacustrine and paludine deposits at Nasariyeh. 

 They agree well with specimens from northern Palestine. The species 

 is common in Syria, the Lake of Tiberias and Lower Mesopotamia. 



Bithinella palmyrae, Dautzenberg. 



1894. BilhincUa 2>ulinyrae, Uautzenbcrg, Rev. biol. Nord France VI, p. 348, 

 fig. 4. 



Several shells, of which only one is complete, from the old lake-basin 

 at Nasariyeh seem to agree with Dautzenberg's figure. The species is 

 otherwise known only from Palmyra in the Syrian desert. 



