SUBEMARGINULA. 279 



1851, p. 88.— C. annullata Ad., P. Z. S. 1851, p. 88.— C. scabricula 

 Ad., P. Z. S. 1851, p. 88.— E. fungina Gld., Proc. Bost. Soc. ii, p. 

 154, 1846 ; Exped. Atlas, f. 491. — E. conoidea Reeve, Conch. Syst. 

 ii, p. 23. t. 140, f. l.— C. acuminata Ad., P. Z. S. 1851, p. 88, no. 10. 



The primary ribs are not split or double, and beween them there 

 are three smaller riblets, the central one often largest ; sometimes 

 some of the primary ribs are suppressed on the side-slopes. The mar- 

 gin is very finely crenulated, the denticles numbering 60 to 72 in 

 all. The picture of a mushroom is usually distinctly outlined in 

 dark green or olive, in the interior. Anal groove rather deep, 

 notch short. The basal margins are level, sides not arched upward, 

 margin not noticably thickened. 



There is a variety in which the riblets are subequal. 



S. papilionacea Nevill. PI. 41, figs. 34, 35, 36. 



Ovate-elongate, subconic, moderately elevated, thin, white ; apex 

 subcentral-posterior, acuminate and incurved ; surface ornamented 

 with fifteen strong subtuberculate or scrobiculate radiating riblets, 

 with numerous smaller ones interposed ; anterior fissure moderately 

 cut, subnarrow. Inside shining, lightly radiately sulcate ; muscu- 

 lar impression quadripartite, two anterior parts much smaller than 

 the posterior, all triangular, converging. Length 12], diam. 9 mill. 



The internal impression bears a striking resemblance to a butter- 

 fly ; the shell is sufficiently transparent for it to be clearly discern- 

 ible from the exterior. (Nevill.') 



S. province of Ceylon. 



Eviarg. papilionacea G. & H. Nevill, Journ. Asiat. Soc. Beng. 

 xxxviii, p. 161, t. 17, f. 12, 1869. 



S. brevirimata Deshayes. PI. 41, figs. 47, 48. 



Shell conic, base rounded-ovate ; apex subcentral, inclined back- 

 ward ; white, 4 or 5 radiate with green ; longitudinally ribbed, 

 riblets unequal, alternating; transversely rugose; larger radiating 

 ribs about 25 in number. Front riblet more prominent, convex, 

 scarcely scaly, ending in a very short slit. Interior white, marked 

 with a pale chestnut spot at the apex. 



Length 7, width 5, alt. 3 mill. (Dh.) 



Is. of Reunion. 



E. brevirimata Dh. Moll, de Pile Reunion, p. 46, t. 6, f. 17, 18, 

 16a. 



