230 



ON THE TOPOGRAPHY AND GEOLOGY 



C. catenatus. Sby., Quart. Joiir., Vol. VI., p. 43, pi. 11, fig. 2. _ . " ' ' ■ 



C. intevatinctus, Guppy. Loc. cit.. Vol. XXII., p. 388, pi. 16, fig. 3. ^' 



Sowerby's description is from a young shell and Guppy's from an adult. I have 

 duplicates of both figures, and a full connecting series. It is not impossible that 

 this may also inchide the form described by me as C. Floridanus, in the American 

 Journal of Conchology, although none of the fossil specimens agree exactly with my 

 recent shell. The points of resemblance are — general form and details of surface, 

 but the only specimen I have seen of C. Floridanus is perfectly straight from the 

 angle to the anterior end, while all of the fossils arc slightly curved. ' : . 



C. stcuo stoma. Shy., Quart. Jour., Vol. VI., p. 44. , ■ , • - . 



/(/., Guppy. Loc. cit.. Vol. XXII., pi. 287, p. IG, fig. 2. - , ' . .. ' - 



Approaches C. toniatus, Brod. in form. . ■ ; 



C. Orbiguyi. Audouin, Mag. de Zool., 1831, pi. 20. y 

 C. pliinicostatus, Sby. Conch , 111., No. 15. 



C. gracilissinms, Guppy. Quart. Jour., Vol. XXII., p. 288, pi. 16, fig. 4. 



Varies slightly in proportionate height and width ; young specimens beiug more 

 slender than older ones. The number of the revolving ri])s is also variable; 

 one of my specimens showing nearly tAvice the usual number, while in a fragmentary 

 specimen, having all of the other characters, of size, shape, elevated and coronated 

 spire, number of whorls, &c,, the surface is nearly plain, being only marked by faint 

 revolving ribs, showing a marked beading. '' • ' 



The localit}^ of the recent shell has been heretofore in doubt. Audouin says his 

 specimen ])robably came from China, and a recent specimen in the Jttuseum of Phil- 

 adelphia Academy is also without a local label. But finding the species fossil in the 

 West Indies Avould induce us to look for its living representations either in the Carib- 

 bean or Panama region, rather than in the Eastern seas. 



C. luarginatus. Sby., Quart. Jour., Vol. VI., p. 44. 



A well-marked species having no close allies. Its broad short form, deep revolv- 

 ing sculpture and high non-coronate spire at once distinguish it. 



C. mus. Huass, Euc. Meth., Vol. I., part 2, p. C30. ' • 



Four specimens only Avere found, but they are unmistakably members of this well 

 known West Indian species. . ■ . 



C. pi a n il i r a t u s . Sby., Quart. Jour., Vol. VI., p. 44. -., _ . , ' . . 



Id, Guppy. Loc. cit., Vol. XXII., p. 287, pi. 16, fig. 7. 



('. Stearnsii, Con. Amer. Jour. Conch., 1869, p. 104, pi. 10, fig. 1. 



A long narrow species, characterized by revolving impressed sculpture. The tops 

 of the revolving ribs are smooth, but in the intervening grooves the lines of growth 

 are elevated, producing a tendency to puuetate chara<3ter similar to that observable 



