HELIX-SNAIL. 107 



OBSERVATIONS ON THE SHELL AND ITS 

 INHABITANT. 



The shape of the Helix varies considerably : 

 some of the species exhibit quite a turreted 

 form ; * in others the whorls are arranged on a 

 horizontal plane,")* so that the spire is quite flat- 

 tened, and the course of the volutions may be 

 seen either from the upper or under part of the 

 shell. Many display a form between these two 

 extremes ; others again are turbinate, and of a 

 globose appearance. J 



There is not, perhaps, any thing in animated 

 nature more abundant or universally diffused 

 than snails ; the butterfly alone can compete with 

 them in this respect. They are found in the 

 most barren and desert wastes : there are parts of 

 the great Sahara destitute of all manner of her- 

 bage, except here and there a tuft of course grass, 

 or a solitary stunted laurel, which according to 

 the Psalmist's description, " withereth before it 

 be plucked up : " yet even these parched speci- 

 mens of vegetation are sometimes quite studded 

 with snails. It has often been conjectured, that 

 snails were in part the food of the Israelites, 

 when they took their rapid flight from Egypt ; 

 for the country, through which they passed in 

 their way to the Red Sea, is described by one 



* Plate V. figure 3. f Plate V. figure 2. 



J Plate V. figure 1. 



