BULIMUS. 237 



3. B. obscu'rus"^^ Miiller. 



Helix obscura, Miill. Verm, Hist. pt. ii. p. 103. B. obscurus, F. & H. iv. 

 p. 90, pi. cxxviii. ff 7. 



Body of a lighter colour than that of B. montanus, with the 

 tubercles comparatively more prominent : mantle larger and 

 more tumid in proportion to its size : tentacles less thick and 

 conical; upper pair finely, but distinctly, granulated, with 

 globular bulbs, which are dilated at the top ; lower pair mi- 

 nutely speckled with black : foot very delicately and slightly 

 fringed, narrow and angular in front, very broad behind, and 

 ending in a rather slender and pointed tail. 



Shell much resembling that of the last species, except in 

 size ; but differing also in the following particulars : — this is 

 shorter in proportion and more glossy ; it has no spiral lines, 

 but instead of them the transverse striae are divided by very 

 minute intermediate lines, and the surface consequently' has 

 not the slightest appearance of being shagreened : ivliorh only 

 62 and more convex : spire more abrupt : suture deeper : 

 mouth proportionally larger : outer lip more reflected and not 

 so thick, plain white, and much more inflected above : umhi- 

 licus a little more contracted. L. 0-35. B. 0-15. 



Var. alha. Shell white or colourless. 



Habitat : On the trunks of trees and among dead 

 leaves in woods, on hedge-banks and old walls, under 

 stones in rocky places, and sometimes in gardens, from 

 the Moray Firth district to South Devon, as well as in 

 South Wales and Ireland. It is much more generally 

 diffused than the last species. The variety has been 

 found by Mr. Smith at Sevenoaks in Kent ; and I have 

 observed it at Lulworth in Dorsetshire. My collection 

 contains a monstrosity, in which the mouth had been 

 broken and renewed in such a manner as to be much 

 stronger than it was before the fracture. This species 

 is in Mr. Brown^s list of upper tertiary shells from Cop- 

 ford. It ranges from Siberia, through Finland, Sweden, 



* Concealed. 



