Trochidae and Turbinidae 111 



Genus COCHLIOLEPIS Stimpson, 1858 

 Cochliolepisi9" striata (Stimpson) Ball PI. 22, fig. 142C 



Alt., 1.3 mm.; greatest diam. of base, 7.25 mm. Shell auriform, 

 greatly flattened, widely umbilicate, thin and horn-colored; nuclear 

 whorl and apex not elevated; two rounded whorls increasing in size 

 to aperture which is expanded and oblique with posterior portion of 

 sharp outer lip somewhat prolonged over shoulder of body whorl; 

 interior of aperture smooth and shining; external surface engraved 

 with fine parallel striations. 



This mollusk is parasitic upon certain annelids. 



Family TURBINIDAE 



Genera of the family Turbinidae are native to tropical and sub- 

 tropical seas. The animals somewhat resemble the trochids in the 

 possession of palmettes and the lateral cirri. They are herbivorous, 

 and confined by this habit to depth zones in which marine vegeta- 

 tion can flourish. Their principal food is said to be marine algae. 



The shells are rather heavy and solid, turbinate or trochiform 

 in shape, not umbilicate; external surface is rugose or smooth with 

 thin epidermis; the aperture rounded, oval or subtetragonal with a 

 simple lip. Operculum is calcareous, flat on inner surface, externally 

 convex. 



Genus TURBO Linne, 1758 

 Turbo castaneusi9* Gmelin PI. 22, fig. 143 



Alt., 30; diam., 25 mm. Shell oblique-ovate, solid, with thin 

 periostracum; color varies through gray, orange and chestnut 

 brown, usually maculated with darker or lighter markings on light 

 or dark background. Spire conic, about one-third of altitude; five 

 or six rounded whorls; sutures channeled; sculpture of strongly 

 beaded spiral lirae of varying size, with fine incremental lines in 

 interspaces; aperture nearly circular, nacreous within; outer lip 

 sharply crenulate; columella white, with white callus; peristome 

 continued below; not umbilicate; operculum calcareous, inner surface 

 flat, chestnut color; convex externally and often stained with a 

 green or brown tint. 



193 Gr., cochlias, snail, snail shell; hpis, scale. 

 1"* Lat., turbo, a top ; castanea, chestnut. 



