94 OBSERVATIONS ON THE BftlTISH 



country is rather a low, open, and extensive valley ; the subsoil 

 almost entirely composed of gravel, in which are not unfrequently 

 found good specimens of jasper and agate. The Ashby Canal and 

 River Sence, with one or two small brooks, run through the parish, 

 and from the predominance of water, and the absence of lime, the 

 greater number of the species met with are such as are peculiar to 

 ponds, rivers, low marshy situations, and wet ditches; and it is 

 amonjr the silt and dead leaves which are left on the banks of the 

 streams after the subsidence of a winter flood, that I find the greater 

 number of shells. A careful examination of such a heap has not 

 unfrequently produced as many as twenty different varieties, and 

 the majority generally in a good state of preservation, and immedi- 

 ately fit for the cabinet, as the snail has been devoured by the nu- 

 merous minute insects and worms which are continually preying 

 upon them. I enumerate the following list of those I have already 

 discovered, though I do not doubt but tliat eight or ten more might 

 be added to it by a more careful research. 



Catalogue of British land and fresh-water Shells, discovered during 

 the winter, in the neighbourhood of Congersto?ie, Leicestershire. 



Cyclas cornea, C. pusilla, — River Sence and Carlton brook. 



Anodon cygneus, — River Sence and Ashby canal. 



Fine specimens of this shell, as much as six inches wide, have been 

 found in ponds belonging to Mr. Cope, at Osbaston, in this neigh- 

 bourhood. 



Mysca pictorum, M. ovata, — Ashby canal. 



ViTRiNA PELLUCiDA, — Low grounds adjoining the Carlton brook. 



Helix nemoralis, H. hortensis, H. aspersa, — In hedges and 



gardens; Helix nitens, H. lucida, H. hispida, H. 



crystallina, H. pygm^a, (rare), H. fulva, (rare), H. 



pulchella, — Left on the banks of the Carlton brook, among 



sedges and dead leaves, after the subsidence of a flood. 



Turton makes two varieties of H. pulchella, the one quite smooth 

 and glossy, the other with regular oblique raised transverse striae ; 

 he also well remarks, that it may still be doubted whether these two 

 varieties may not be considered as distinct species. In this point I 

 am inclined to agree with him, for I have never yet discovered the 

 two varieties in the same locality. Turton also remarks, that, in 

 the dry hills around him, (Bideford, Devon), he finds the smooth 

 variety in al)undance, but never any with the epidermis or trans- 



