1921.] B. Prashad : Siiiiiatran Molluscs. 477 



pullaria. Lam., by the structure of ihe operculum and the inhal- 

 ent siphon. In Pachylabra the operculum is a massive calcareous 

 structure with a coarse external horny covering, while the siphon, 

 when expanded, is a funnel-shaped structure considerably broader 

 than long, when contracted it is a prominent fold on the left side 

 of the head forming an incomplete tube not much longer than its 

 transverse diameter. 



Pachylabra conica (Gray). 



1828. AinpriUaria conica. Gray, Snpp. Wood's Index Test., pi. vii, fiy. 

 22. 



1848. Ampullnria orientalis, Pliilippi, Zeitschr. Malakozool .. p. 192. 



1849. Ampiillaria sciitata, Mousson, Moll. 'Java, p. 60, pi. \ii. fisj. 2. 

 1851. Ampullayia sciitata, Ph\Y\p^\. Marl. Cliein. Conch. Cab., p. 9, 



pi. i. figs. 4, 5. 

 1854. Ampiillaria conica, Hanley, Conch. Miscell., pi. iii, fig. i:j. 

 1B54. Ampiillaria conica, and A. Javanica, Reeve, Conch. Icon., pi. ii, 



fig. 10 ; pi. XX, fig. 26. 

 1857. Ampiillaria sciitata, v. Martens. Malakozool. Blatt., p. 186. 

 1877. Ampiillaria conica near type form, var. orientalis and 1 borneen- 



sis. Xevill, Cat. Moll. Ind. Mas. Fas. E., pp. 7-10. 

 1S85. Ampiillaria conica typical form. vars. orientalis and ? borneensis, 



Nevill, Hand-List Moll. Ind. Mus. II, p. 5. 

 iSgo. Ampiillaria conica var. Javanica, Boettger, Ber. Senckenb. 



Natiirg. Ges., p. 156. 

 1897. Ampiillaria sciitata v. Martens, op. ctt., pp. l8. 19. 

 189S. Ampiillaria sciitata, Sarasin, P. and F., .Iloil. Celebes, I, p. 69. 



1910. Ampiillaria conica, and vars. borneensis, Javanic.i, orientalis and 



sciitata, Sowerby, Proc. Malacol. ioc. London, IX, pp. 57, 58. 



191 1. Pachylabra conica, and P. ja-janica. Ivobelt, op. cit., pp. 93, 94, 



S3, 84. pi. XI., figs, 1-5, 8, 9, and pi. xxxv, figs. 5. 6. 

 1913. Ampiillaria sciitata, Schepinann, Proc. Malacol. Soc. London, X, 



p. 236. 

 1915. Pita conica and var. orientalis. Preston, Faun. Brit. Ind. 



Freshiv.-Moll., pp. 100, loi. 

 1920. Pachylabra conica. Annandale, Joiirii. Nat. Hist. Soc.Siam, I\', 



pp. 9, 10, pi. i, fig. 3 and pi. ii, fig. 2. 



The above fairly complete synonymy is given in view of the 

 great differences of opinion that have existed regarding the form 

 named Anipullaria conica by Gray. Von Martens considered the 

 name conica, as used in Wood's Index, as being too doubtful to 

 apply to the Javanese species. There remains no doubt, however, 

 if we take Hanley's figure, which is a delineation of Gray's type, 

 as representing conica. I have, therefore, with Sowerby adopted 

 Gray's name in preference to Mousson' s sciitata, though I do not 

 agree with Sowerby in considering lubrica, stoliczkana ' and turbi- 

 noides as varieties of this species. The forms orientalis, borneen- 

 sis and javanica certainly belong to it. Philippi and Kobelt re- 

 gard the latter two as distinct species, but an examination of the 

 collections in the Indian Museum does not uphold their conclusions. 

 The specimens of these forms show a clear gradation towards conica, 

 and must be assigned to it. Owing to the paucity of material 



' Most authors seem to have missed Nevill's paper (Journ. As. Soc. Bengal . 

 L. pt. ii, p. 155, pi, vi, figs. II, ha) in which he gives good figures of this interest- 

 ing species. 



