MOLLUSCA or IXDIA. 



241 



would have been far less satisfactory. There is in fact a wealth 

 of material to be described, not only in this genus but in others. 

 As work proceeds eastward into the Eastern Himalaya, Assam, 

 Burma, and the Shan States, practically unworked areas are 

 I'eached, and new species multiply, in most cases of those shells 

 which have been collected; the animals that formed them are 

 unknown. Species of Macrochlamys are without exception the 

 most difficult to determine; only those conchologists who have 

 worked at them, know how subtle and unfixable are the shell 

 differences, and can form any idea what labour is entailed. The 

 animals, however, greatly assist in the determination of species ; 

 future collectors will do well to note the colour, external form and 

 markings, and preserve the animals for dissection. I may here 

 point out as a remarkable and unexpected instance of divergence 

 in internal anatomy, not borne out to the same extent in the 

 form of the shells, the two species M. cacliarica aiid M. atricolot' 

 display in their generative organs (Vol. I. p. 117). 



1 would allude here to a paper in the 'Proceedings of the 

 Malacological Society,* vol. vi. (1905), p. 319, on the extension of 

 this genus to the island of Mauritius, founded on specimens col- 

 lected there by Monsieur E. Dupont. At the time I received them 

 I had no Indian species the shell of which was quite comparable ; 

 since then specimens sent me by Mr. F. Ede from Cachar, described 

 further on as M. indica, var., are so very similar in general 

 character that I have been led to consider the Mascarene species 

 was possibly introduced by the agency of man from some part of 

 the Gi-angetic delta. 



Genus Macrochlamys. 



Shell smooth, sufx/lobose or suhglohosely depressed; 

 columellar margin vertical or subvertieal, 



Macrochlamys subjecta, Bs. 



(Helix) A. M. N. H. (2) ix. 1852, p. 407 ; Pfr. (ffelLr) Mon. Hel. 

 iii. 1853, p. 48 : H. & T. {IJeliv) C. J. 1876, pi. 64. figs. 1, 2, 3 ; 

 NeviU, Hand-1. i. 1878, p. 25. 



In Eauu. Brit. Ind., MoUusca (1908) p. 98, it is thus described :— 



" Shell subobtet-tly perforate, conoidly depressed (subglobose), 

 very thin, smootli, with a rather oily lustre above, more vitreous 

 beneath, pale yellowish amber to yellowish lawny in colour ; spire 

 low conoidal, apex rather acute, suture impressed ; whorls 6-6|, 

 convex above, the last considerably broader, well rounded exter- 

 nally and beneath ; aperture slightly oblique, roundly lunate, 

 broader than high ; peristome very thin, in one plane ; columellar 

 maro-in much curved, becoming vei'tical near the perforation and 

 triangularly expanded, but very little i-eflected. 



" Maior diam. 10, min. 13, height 9 mm. 



y2 



