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Chapter VII. 



THE EDIBLE SNAIL. Helix pomatia. 



The snail is a terrestrial animal, feeding on leaves and other 

 vegetable matter which it rasps off with its toothed tongue 

 or odontophore. The dorsal surface of the body carries a 

 spirally coiled univalve shell, which lodges most of the viscera, 

 and within which the entire animal can be withdrawn for 

 protection. It breathes air by means of a pulmonary chamber, 

 formed by a fold of skin — the mantle — on the dorsal surface. 

 It is hermaphrodite, but incapable of self-fertilisation. 



The edible snail occurs in many parts of England, and 

 can be readily obtained from dealers. On account of its large 

 size it is preferable to the commoner English species, H. 

 aspersa, to which, however, the following description will 

 apply with but slight modification. 



Snails are best killed by putting them in cold water and 

 then running a layer of very hot water on to the surface, when 

 they die in an expanded condition in about two hours. In 

 winter the mouth of the shell is closed by a plate of hardened 

 mucus, the epiphragm, which must be removed before putting 

 the snail in water. When dead the snail should be put into 

 spirit for a short time before it is dissected, in order to facilitate 

 the removal of the mucus. 



I. EXTEENAL CHAEACTERS. 



A. Before Removal of the Shell. 



1. The shell is a right-handed conical spiral, each turn of 

 which overlaps and conceals the greater part of the 



