IN A SNA1LERY. 23 



aperture a* film of slimy mucus, which hardens, as tight as 

 a miniature drum-head. As the weather becomes colder, 

 the creature draws itself a little farther in, and makes an- 

 other u epiphragm," and so on until often five or six pro- 

 tect the animal sleeping snugly coiled in the deepest re- 

 cesses of his domicile. 



This state of torpidity is so profound that all the ordi- 

 nary functions of the body cease respiration being so en- 

 tirely suspended that chemical tests are said to discover no 

 change from its original purity in the air within the epi- 

 phragm. Tims the snail can pass without exhaustion the 

 long cold months of the north, when it would be impossi- 

 ble for it to secure its customary food. This privilege of 

 privacy reminds me of an old distich about another hiber- 

 nater : 



"The tortoise securely from danger does well, 

 When he tucks up his head and his tail in his shell." 



The reviving sun of spring first interrupts this deep 

 slumber, and the period of awakening is therefore delayed 

 with the season, according to the varying natures of the dif- 

 ferent species. A few species, however, seem to hibernate 

 very little, vitrina, for example, having been seen active in 

 cold weather, and even crawling about in the snow ; while 

 the finest American specimens live high up on the -Rocky 



