420 Records of the Indian Museum. [Vol. XVI, 



contains are of large size, very compact and somewhat spindle- 

 shaped. 



The most remarkable feature of the anatomy lies in the fact 

 that there is no intromittent organ in the male. The lower part of 

 the oviduct and of the vas deferens is alike a simple tube opening near 

 the anus on the right side of the body. We have satisfied our- 

 selves of this fact by dissecting a considerable number of specimens, 

 of which we have also examined the gonads microscopically. 

 Unfortunately the condition of our material renders it impossible 

 to investigate the genitalia further. 



Heude {of cit., 1890, pi. xxxiii, fig. lie) reproduces a figure of 

 the central nervous system drawn by Rathouis. It shows the whole 

 structure as being compact with rather short commissures. The 

 optic nerves are, however, long. The otocysts are situated just 

 in front of the supraoesophageal ganglia. Each otocyst, as we 

 have satisfied ourselves, contains a single circular otocyst. 



Imperfect as is this description of the anatomy of Fenoiulia^ 

 it is sufficient to prove its wide divergence from the Hydrobiid 

 type. 



Genus Paraprososthenia, Annandale. 



1919. Paraprososthe)iia, Annandale, Rec. Geol. Surv. Ind. L (3), pp. 209-240. 

 This genus, although it closely resembles Prososthenia, Neu- 

 mayr, from the Miocene beds of Eastern Europe in form of shell 

 differs in sculpture and in the structure of the lip, which is thin 

 and somewhat expanded instead of thickened and contracted. 

 Nothing is known of the soft parts, radula or operculum, but the 

 shape of the shell and the structure of its mouth are so close to 

 those of the new species here described that we think they must 

 be united, notwithstanding certain obvious differences, as sub- 

 genera of a single genus. For the new subgenus we propose the 

 name ParaPyrgula in allusion to the resemblance, probably quite 

 superficial, between the shell and that of Pyrgula from central 

 Europe and the eastern parts of the Mediterranean basin. 



Parapyrgula, subgen. nov. 



The shell is elongate, narrow, strictly conical, with the base 

 rounded and somewhat produced. Its substance is delicate and 

 fragile but not very thin. There is a very delicate periostracum. 

 The suture, which is sometimes almost obsolete externally, has a 

 peculiar involute structure owdng to each whorl growing over and 

 pressing closely round the base of the one preceding it. The shell is 

 imperforate. Its mouth, w'hich is not very oblique, is of moder- 

 ate size and of distinctly pyriform outline, slightly produced pos- 

 teriorly. The peristome is continuous and there is a rather thick 

 columellar callus, but the outer lip is thin. The only prominent 

 sculpture is a single smooth spiral ridge on the body whorl. 



The operculum resembles that of Fenouilia. 



The radula is also similar to that of that genus, but the denti- 

 culations of the teeth are for the most part longer and more 



