Gaspard's Memoir, SfC. 93 



Helix incamata. 



pubescens. 



cespitum. 



ericetorum 



villosa. 



hispida. 



lucida. 



conspurcata. 



striata. 



plebeium. 



lapicida. 



obvoluta. 



pulchella> 



nitida. 



Helix nitidula. 



rotundata. 



crystallina. 



Vitrina pellucida. 

 Testacella haliotoidea. 



Limax scutellaris. 

 Cyclas cornea. 



lacustris 



fontinalis. 



Unio pictorum 



littoralis. 



Anodon anatinus 



cygneus. 



Art. XIV. — Abstract of a Memoir on the Phi/siologi/ of 

 Helix Pomatia. By B. Gaspard, D. M. ; with Notes 

 «>y T.Bell, F. L. S. 



§. 1. lu our temperate climate, about the beginning of October, 

 as the first chills of autumn are felt, these Helices become indo- 

 lent, lose their appetite, and associate in considerable numbers 

 on hillocks, the banks of ditches, or in thickets, hedges, &c. In 

 a day or two they cease to eat, expel the last contents of the in- 

 testines, and then conceal themselves under moss, grass, dead 

 leaves, &c. Here each forms for itself, with the anterior part of 

 its muscular foot, a cavity sufficiently large to contain at least its 

 shell ; this it enlarges and excavates by turning itself round on 

 every side, then raising itself against the sides of the cavity, and 

 at last against the roof formed of moss or leaves, or a small quan- 

 tity of earth brought there by the motions of the animal. When 

 it has got so far as to bring the opening of the shell to nearly a ho- 

 rizontal position, it ceases. It soon contracts the foot within the 

 shell ; expands, so as completely to cover it, the collar of the 

 mantle, which is at this period of a very white colour, and opens 

 for a time' the pulmonary cavity to inspire a quantity of air. On 

 closing this, it forms with the mucus, a fine transparent membrane, 

 interposed between the mantle and such extraneous substances ly- 

 ing above as might be injurious. Soon afterwards the mantle se« 



* From Majcndie'* Journal de IMiysiologie, torn, ii, p. 295. 



