1865.] Contributions to Indian flfalacohgy. 81 



But a solitary specimen was met with belonging to this form, which 

 is more tumid in the centre than any of its allies, C. insignis, Gould, 

 &c. The non-continuity of the peristome may be due to immaturity 

 in the specimen found. The shape of the mouth may also possibly be 

 slightly modified in older examples, but the general form doubtless 

 remains the same, and is alone sufficient to distinguish the species. 



A solitary specimen of another new form, much smaller than the 

 above, being only 17 millem. long, occurred at Moditoung Tsekan, on 

 the road from Prome to Tongoop. It is unfortunately bleached and 

 worn, though perfect. 



Genus STREPTAXIS. 



23. S. Burmanica, n. sp. 



Shell ovately subglobose, umbilicated, thin, horny, white, marked 

 throughout with fine and closely set sinuate costulation. Spire 

 convex ; sutures scarcely impressed. Whorls G, the last 2 widely 

 excentric, rounded at the periphery ; the penultimate broader than the 

 last whorl ; last flattened beneath, and angulately compressed around 

 the umbilicus. Aperture oblique, irregularly semioval, with a single 

 re-entering lamellar parietal ; peristome white, thin, expanded through- 

 out, deeply sinuate above, at the junction with the penultimate whorl, 

 compressed and curved forwards on the upper right margin, and some- 

 times furnished with a veiy small internal tooth-like callous projection ; 

 the two margins subparallel, distant, united by a thin callus. 



Millem. inch. 



Major diameter, 10 0.4 



Minor ditto, ,. 7 0.28 



Height, 6 0.24 



Habitat — Tongoop, Arakan. 



This is a very near ally of the Molmein S. Petiti, Gould, but it ia 

 distinguished from that shell and from S. exacuta, Gould, by the 

 rounded periphery and more globose form. It is larger and less 

 slender than S. Andamanica, Bens., and is distinguished from all the 

 above species, and also from the Nilgiri 8. Perrotteti, by the greater 

 size of the penultimate whorl in comparison with that of the antepenul- 

 timate, a character to which my attention was called by Mr. Benson. 



In Dr. Gould's original description (an imperfect one) of S. Petiti. 



