3(>6 NATURALIST'S CABINET. 



Water snails Esculent snail. 



There are about fifteen kinds of the sea snails, 

 eight of the freshwater snail, and five of the 

 land snail, all of which bear a strong resem- 

 blance to the garden snail. The water snails, 

 however, both river or sea, are found in some 

 things to differ very materially. In the first 

 place, all snails which live in water a r e furnished 

 by nature with a contrivance that enables them 

 either to rise to the surface, or sink to the 

 bottom of the water ; this is performed by open- 

 ing and shutting the orifice on the right side of 

 the neck, which is supplied with muscles for that 

 purpose. The snail sometimes gathers this aper- 

 ture into an oblong tube, and stretches it above 

 the surface of the water, in order to draw in or 

 expel the water, as it finds occasion ; by dilating 

 it this animal rises, and by compressing it sinks 

 to the bottom. Some are also found viviparous, 

 while others lay eggs in the usual manner ; and 

 the former not only bring forth their young 

 alive, but with their shells upon their backs ; 

 which, strange as it may appear, has been in- 

 contestibly proved by an experiment of Swam- 

 merdarn. 



Among the Romans the esculent snail consti- 

 tuted a favorite dish ; but, according to Varro's 

 account, who says that the shells of some of them 

 would hold ten quarts, they had it of a size infi- 

 nitely larger than any now known. 



