TESTACELLA. 87 



The TestacellidcE form the connecting link between 

 the Limacidcs and the Helicid(E\ their bodies, though 

 not entirely naked like those of the former, are nearly 

 so, and they resemble the latter in their shell being 

 external The family is represented by a single 

 genus. 



TESTACELLA* CUVIER. 



Body slightly granulated, sides or corners of the Hps capable 

 of being protruded, causing the animal to appear as if it had 

 three pairs of tentacles ; tentacles 4, cylindrical ; eyes placed a 

 little above the centre of the tips ; foot provided with a prominent 

 margin. 



Shell thick ; spire minute, forming one half of a whorl. 



The snail-slugs differ from all the other land mol- 

 luscs (with the exception, perhaps, of Achatind) in 

 being exclusively carnivorous ; their food chiefly con- 

 sists of earthworms, which they attack with relentless 

 ferocity, following them through their subterranean 

 burrows, and, if need be, cutting off their retreat by 

 countermining ; the unfortunate victim is devoured 

 alive, being drawn into the mouth of the slug by the 

 formidable array of curved and barbed teeth with 

 which it is furnished. 



This savage creature feeds at night, and if its usual 

 food is not forthcoming it will devour other slugs, as 

 well as snails, and even its own species. When its 

 ravenous appetite has been appeased it remains for a 

 considerable time in a lethargic state. Though it is 

 exceedingly hardy, and suffers but little from the 

 cold, in very severe weather it forms a cocoon of 

 particles of earth which are cemented together by its 



* Little shell. 



