DENT ALIUM-FUSTI ARIA. 129 



Length 35, antero-posterior diam. aperture 3*4, lat. diam. 3*2 ;. 

 diam. of apex 0'6 mill. 



Length 34'5, antero-posterior diam. aperture 3*5, lat. diam. 3*4 ^ 

 diam. of apex 0'5 mill. 



West Indies. 



D. translucidum Desh., SOWERBY, Thes. Conch., iii, p. 98, pi. 225, 

 f. 47 (1860) ; Conch. Icon., xviii, pi. 6, f. 39 (1872). Not D. trans- 

 lucidum Desh., 1825. 



Distinguished by its rapidly tapering form, the smoothness of its 

 glittering surface, with no trace of stride even at the apex, and the 

 long linear slit of a Fustiaria. D. translucidum Desh. is an unslit 

 species and less attenuated toward the apex. Types in Coll. A. N. 

 S. P., no. 71081. 



Fig. 13 shows the actual length of the slit. Figs. 10, 11 are en- 

 larged ventral and dorsal views of the apex. Fig. 15 is an old shell. 



D. TENUIFISSUM Monterosato. PI. 19, figs. 16, 17. 



This form is much like D. rubescens except that there is a very 

 long, linear slit on the convex side. We have followed Jeffreys in 

 treating it as a variety of D. rubescens (see p. 106) ; but the form is 

 more likely to prove a distinct species of Fustiaria. 



