EIBERNATION, i6i 



total suspension of vital forces in reptiles to that which 

 vegetation undergoes. Circulation stops, the juices become 

 stagnant, whether in a tree or in a snake, and it is sometimes 

 difficult to decide in either case whether life is extinct or 

 not. But with returning warmth comes renewed vitality ; 

 the fluids, whether of the animal or the vegetable organism, 

 are thawed by the revivifying solar rays, which set them 

 circulating and start the pulsation; and the animal machinery, 

 like a watch wound up, is set in working order again. 



It is owing to this lack of warmth in themselves that 

 snakes can live only in hot countries, or in cooler latitudes, 

 during the warmer weather, and not at all in the frigid 

 zones. In speaking of them, Dumeril says Linnaeus was 

 right in calling them cold animals in hot countries. * Aussi 

 la plupart des Ophidiens habitent-ils les climats chauds, 

 et c'est en parlant d'eux que Linne a pu dire avec raison : 

 " Frigida a^stuantium animalia." ' ^ 



Dumeril describes their respiration as arbitrary, suspended, 

 retarded, or accelerated at will. ' La respiration ctant volon- 

 tairement acceleree ou retardee, les actions chimiques et 

 vitales qui en resultent doivent etre naturellement excitees 

 ou ralenties par cette cause.' ^ ' The electric fluid,' says 

 Latreillc, ' is one of the great agents in animating living 

 beings ; and upon reptiles it operates in conjunction with 

 warmth in rousing them from their inactivity.' 



The periodical torpor and insensibility which reptiles 

 undergo cannot, however, be always associated with extremes 

 of cold, nor in all cases called strictly a ^luiutcr' sleep; 



^ Erpetologie genci-aIe,\.OTtit\\. p. 1 84. 

 ^ Ibid, tome i. p. I So. 



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