132 



POPULAR CONCHOLOGY. 



is almost cylindrical, delicately curved, with suddenly 

 diminishing whorls or spire, which is easily broken off ; 

 the operculum circular, horny and spiral. — Marine. 



Ccecum. Flem, (Brochus Bronn; Odontina Zborzew- 

 ski; Odontidium Phil,; Ccecalium Macgil.) — Shell rather 

 cylindrical, more or less curved, tubular, closed at one 

 end, where the younger portions or original 

 spire has been broken off, open at the other, 

 where the aperture is entire ; operculum horny, 

 with many whorls. Animal, when adult, cy- 

 lindrical ; head muzzle-shaped, flanked by Cozcum trachea. 

 cylindrical subulate tentacula, bearing trun- 

 cate eyes on (not on bulgings of) their external bases ; no 

 lateral cirrhi, nor lobes; foot short, narrow, truncate in 

 front, obtuse behind ; no posterior cirrhus ; mantle thick, 

 not fringed ; a single branchial plume ; tongue short, cen- 

 tral denticles, apparently undeveloped ; two uncini on each 

 side, the inner one broad and serrulated.* — 3 ? species ; also 

 fossil. 



Singular little shells, looking somewhat like Dentalium, 

 but they are closed at one end. They are found on the 

 British and Scotch coasts; and the author has received 

 one from Mazatlan, in California. 



Family 26. — SIPHONARIA CEA. 



The animals have a two-lobed head, the eyes placed on 

 the lobes ; no feelers ; a single gill, lying across the neck. 

 The shell is cup-shaped, almost symmetrical, with the apex 

 nearly in the middle. — Marine. 



* Forbes's British Moll. 



