284 HELICIDE. 



distribution is not very extensive; bat it occurs in many 

 parts of France, Germany, and Switzerland. If (as I 

 suspect) this is the same species as that which Malm 

 has referred to the C. lineolata of Held, it ranges north- 

 ward to Sweden. 



This is an inactive mollusk, and seems to drag its shell 

 along with difficulty, as if it were an incumbrance. In 

 its natural state the shell has often a slight covering of 

 mud or dirt. 



It differs from C. Rolphii in its shell being twice as 

 large and much more slender, in the constant presence 

 of white lines or streaks, and in seldom having any 

 interlamellar teeth, but chiefly in the form of the aper- 

 ture and the distinct channel at its base. In the latter 

 respect it also differs from the C. ventricosa of Dra- 

 parnaud. 



It is the C. similis of Charpentier. Another of its 

 synonyms is the C. vivipara of Held ; but I am not 

 aware that the organization of the animal warrants this 

 last specific name. 



B. Shell nearly smooth, glossy : clausillum having its margin 



on the lower side notched. 



4. C. lamina' TA*, Montag*u. 



Ttirho laminatus, Mont. Test. Brit. p. 359, tab. ii. f. 4. C. Uminata, 

 F. & H. iv. p. 116, pi. cxxviii. f. 10. 



Body slightly narrowed and nearly truncate in front, gradu- 

 ally attenuated and rather pointed behind, reddish-black or 

 greyish-brown, with a yellow tinge on the upper part, light- 

 grey on the sides and underneath ; tubercles somewhat large 

 and prominent, more or less .deeply coloured : mantle not 

 reaching the mouth of the sheU, annular and narrow, covered 

 with minute and indistinct black dots : tentacles rather short, 

 thick and diverging, reddish-brown ; upper pair very finely 



* Having plates. 



