UROCOPTIS, S. G. GONGYLOSTOMA. 255 



Cyl. canteroiana Gundl. mss., ARANGO, An. Real. Acad. 

 Cienc. Habana, xii, p. 284, sp. no. 15 (1876). 



I do not know the locality, which may be near Guane, or 

 in Santa Clara province. 



Group of U. trilamellata. 



Shell opaque, rib-striate, the riblets light on a dull, pur- 

 plish-brown, corneous-brown or fleshy ground; aperture 

 brown within, a little narrowed above; last whorl more or 

 less free in front; axis with one to three lamellas, the lowest 

 lamella widest. 



Key to Species. 



I. Length 3y 2 to 5 times the diameter. 



1. Axis with 3 lamellae, the upper one small, lower 

 widest. 



a. Stout, rather rapidly tapering above; ashy- 

 flesh colored, the narrow riblets parted by 

 wider intervals; length 15.5 to 24, diam. 4.8 

 to 6 mm. ; whorls 8-10. 



U. vignalensis, no. 137. 



6. Stout, blackish-brown, similar to vignalensis 

 but riblets more widely spaced; length 17, 

 diam. 4.5 mm. ; whorls 9-10. 



U. abdita, no. 138. 



c. More slender ; dull purplish with strong whitish 

 rib-striae half as wide as their intervals; upper 

 lamella very small; length 17.5 to 20, diam. 

 3.4 to 4 mm. ; whorls 9 to 12. 



U. trilamellata, no. 139. 



2. Axis with 2 lamellae; cylindrical, brown, striate- 

 plicate ; length 20, diam. 5 mm. ; whorls 10. 



U. nubila, no. 140. 



3. Axis with 1 thin lamella, 2 hardly noticeable spiral 

 cords above it obsolete in last two whorls; shell 

 tapering above, purplish-brown with narrow, wide- 

 spaced whitish riblets; length 18-19, diam. 4 to 4.5 

 mm. ; whorls 10-12. U. violacea, no. 141. 



