CiECUM. 215 



Genus C^CUM, Fleming, 1817. 

 Section I. Levia. 

 C. L^VE, C. B. Ad. PI. 66, fig. 52. 



Shell rather obese, short, smooth, shining, subdiaphanous, 

 tinged with brown, slightly contracted in front, the aperture 

 oblique ; operculum concave. Length, -07 inch. 



Panama to Mazatlan. 

 Folin has described vars. subornatum and cylindrica. The 

 figure is from a specimen identified by P. P. Carpenter. 



C. FARCiMEN, Cpr. PI. 66, fig. 53. 



Like C Iseve^ but whitish, aperture less contracted, more slen- 

 der, septum submucronate ; operculum with a spiral marginal 

 rib. Length, -064 inch, Mazatlan. 



C. viTREUM, Cpr. PI. 66, fig. 54. 



Subelongate, vitreous, shining, a little tumid towards the 

 oblique aperture, septum prominent, mucronate. 



Length, •078--107 inch. Teneriffe ; Mediterranean Sea. 



C. Sardinianum,FoVm, and C.glabrum,M.c Andrew ^avesynonjms. 

 Var. Clarkit, Carp. PI. 66, fig. 55. 



Shell smaller, straighter, septum ungulate, apex more obtuse. 



Teneriffe. 

 C. DEXTROVERSUM, Carp. PI, 66, fig. 56. 



Narrow, rather elongated, thin, septum tumid, submamillated, 



operculum concave. Length, -092 inch. Mazatlan. 



The specimen figured is a junior. 



Var. Antillarum, Carp. 



A single young specimen was found in W. Indian sponge, not 

 presenting any characters by which it can be separated from G. 

 dextroversum. Why should it be designated by a varietal name ? 



C. GLABRUM, Mont. PI. 66, fig. 57. 



Shell narrow, thin, smooth, subdiaphanous, aperture not con- 

 tracted, nor tumid, white, septum without appendage. 



Length, "68 inch. Atlantic Coast of Europe. 



The operculum is externall}^ convex, constituting it the type 

 of Gray's group Brochina. The synonyms include Dentalium 

 minutum, Linn.; Brochus laevis, Brown; Cornuoides minor, 

 Brown (juvenile); Odontidium levissimum, Cantr. ; Brochus 

 arcuatuSj Brown ; Vermiculum incurvatum, Mont. 



