35S 



OJ 



feftly detached from it ; and at the back of the lower 

 volution, behind the mouth, is a prominent ridge, and 

 a dcprefTion. Length rarely half an inch ; breadth one 

 fourth its length. 



This fpccies is the mofl common of all the Britijk land 

 fliells : it is found in every part of the kingdom in woods, 

 and fhady places, particularly on trunks of trees, mofly 

 and ivy-grown walls. In its young (late, before the 

 mouth is formed, it has been confimnded for T. pcrver- 

 Jiis of Linn ^ us: but even in that flate it is readily dif- 

 tinguifhed by the bafe being flattifli, and appears un- 

 formed ; which is never obfcrved in the other at any age, 

 the laft volution being always rounded. In the colour 

 too, it is effeniially different, as in no inftance is it found 

 to be of that light, pellucid, greenifli horn-colour. 



Da Costa, as well as others, has fallen into this er- 

 ror. Donovan has evidently given a figure of this 

 ihell, but is millakenin quoting the T. perverfus of Lin- 

 naeus, as well as making it the Strombiformis perverfus, 

 of D'V Costa. The fliell figured by that author is the 

 T. labiatus of this work, though he erroneoufly defcribes 

 the T. bidens as the young of that (hell. 



This fpecies was called by Doclor Solaxder Turbo 

 '■lig-ricans. 



o 



Animal duflcy *. tentacula four, fliort, cylindric. cla- 



vatc ; 



