340 Shell Life 



in all the .species of the genus, there is an open 

 umbilicus. The animal is slaty-grey in colour, of a 

 shy and retiring nature, and evil- 

 smelling. It will be found under 

 l)rick rubbish in backyards, in cellars, 

 under logs and stones in woods, and 

 in mossy hedgerows everywhere. The 

 Garlic Snail {H.alliaria) is more convex 

 P,M,, ,„ ., and darker above, less white beneath, 



and only a quarter of an inch across. 

 The animal is much darker than H. cellaria, and its 

 tentacles are proportionately shorter; but the shell 

 may easily be confused with that of a half-grown Cellar 

 Snail. Jeffreys' test in such a case is to view the two 

 shells sideways, when the last whorl of alliaria will 

 be found to be less deep than in ceUaria. It is 

 more local than the last named, and must be sought 

 in more open situations, but hidden under stones. 

 Its name is due to the fact that when irritated it gives 

 off an odour of garlic which varies in intensity. 

 Too much importance must not be attached to this 

 characteristic in arriving at the identity of the species, 

 for several of its congeners have the same peculiarity, 

 though perhaps less markedly. It is, no doubt, a 

 protective endowment, for the odour is not perceptible 

 until the snail is interfered with, and continued 

 irritation appears to lessen its pungency. 



The Glossy Glass-snail (J^. glabra) is a little larger 

 than the Garlic Snail, whose odour it shares under cer- 

 tain conditions — as when being killed by the boiling- 

 water method. The animal is bluish grey, with 

 zebra-like stripes in front and mottled behind ; the 

 sides marked with a dark line just above the foot. 



