100 HELIX. 



H. PERDEPRESSA, Adams. PI. 19, fig. 42. 



Widely umbilicated, striulate, diaphanous, corneous-white, spire 

 flat, apex immersed, suture deep ; whorls 4, convex, slowly increas- 

 ing, the last descending in front, periphery subangulated, base 

 inflated. Diam. 5 mill. 



Jamaica, 



H. CYCLOSTOMOIDES, Pfr. PL 19, figs. 43, 44. 



Widely umbilicated, scarcely convex above, concave below, 

 smooth, hyaline ; whorls 4, slightly convex, rapidly increasing, the 

 last depressed, with obsoletely angulated periphery ; aperture sub- 

 circular. Diam. 4 mill. 



Cuba. 



H. PTYCHODES, Pfr. PI. 19, fig. 45. 



Moderately umbilicated, much depressed, discoidal, very thin, 

 arcuately plicate, hyaline under a thin, deciduous, fuscous epider- 

 mis; whorls 4z-5, the base scarcely more convex. Diam. 10'3 mill. 



Jamaica* 



H. TICHOSTOMA, Pfr. PI. 19, fig. 46. 



Widely umbilicated, hyaline, shining, thinly striated ; whorls 5 r 

 somewhat flattened above, narrow T , the last much wider ; aperture 

 with the penultimate whorl partly halved by a horizontal lamina. 



Diam. 6 mill. 



Cuba. 

 H. lamellina, Newcomb, MSS., is a synonym. 



H. STIGMATICA, Pfr. PI. 22, figS. 24-26. 



Umbilicated, thin, yellowish corneous, diaphanous, very min- 

 utely hispid-granulate ; spire flat ; whorls 4j, convex, the last a 

 little descending, rounded ; lip very slightly expanded. 



Diam. 17 mill. 



Cuba. 



H. VELUTINA, Lam. PI. 22, figs. 30-32. 



Perforate, thin, very minutely subreticulately striate, the epider- 

 mis sublamellate, waxy, shining, velvety but not pilose, suture deep ; 

 whorls 5, convex, slowly increasing, the last not descending, with 

 subplanulate base. Diam. 13 mill. 



Porto Rico. 



H. SUAVIS, Gundlach. PL 22, figs. 33-35. 



Narrowly umbilicated, thin, minutely granulate and very shortly 

 pilose, light brownish, spire immersed in the middle ; whorls 



