98 BRITISH MOLLUSKS. 



Hal. Throughout Europe. Algeria. Madeira. (Buried in loose earth, 

 among roots, or under stones.) 



This minute species is a niollusk of very secluded habits, living 

 among roots or under stones, buried, not tinfrequently, several inches 

 in the ground. Its shell is perfectly colourless, and of almost glassy- 

 tenuity, but distinctly characterized by an arched, involute colu- 

 mella, truncated at the end. It ranges throughout Europe from 

 Sweden to the Mediterranean ; and it is more than probable that 

 M. Bourguignat's Ccecilianellce raphidia, tumulorum, Brandellii, 

 subsaxana, nanodea, Syriaca, and nyctelia from Greece, Syria, 

 Algeria, and Madeira, are merely local varieties of it. In Britain 

 it is diffused sparingly throughout England and Ireland, and the 

 Channel Islands, but not in Scotland or the Isle of Man. 



r^ 



Clausula laminata. (Moderately enlarged.) 



Gents IX. CLATJSILIA, Draparnaud. 



Animal ; sometimes rather broad, sometimes narrow, carrying a 

 sinistrally convoluted, cylindrically acuminated shell, foot 

 rather obtuse at the posterior end, head with the upper pair of 

 tentacles stout, clavate, the lower ones small. 



Shell ; sinistral, imperforate, fusiformly tapering, of front nine to 

 twelve whorls, somewhat papillary at the apes, whorls some- 

 times smooth, generally densely wrinkled, last whorl con- 

 stricted, with the aperture small, surrounded by a continuous 

 lip, furnished with teeth and internal thread-like plaits, en- 

 closing a lamellar valve or clausilium. 

 Clausilia is a mollusk of much interest, considered in reference 



