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CHAPTER VI. 

 HIBERNATION AND SLOUGHING. 



GENERAL — IN VARIOUS SPECIES— QUOTATIONS— CRITICISM. 



As the two processes of hibernation and sloughing are 

 common to all serpents, it will be convenient to dis- 

 cuss them in a separate chapter, so that the peculiar- 

 ities of the different species may be contrasted. 



Hibernation. — Hibernation in British serpents 

 means the method they adopt to pass the winter 

 months. It applies to all reptiles which are inhab- 

 itants of cool climates. It is precisely comparable to 

 the process of aestivation, which is the summer sleep 

 of reptiles in tropical countries, where the serpents 

 retire in the dry season, to become active again when 

 the rainy season begins. In cool countries, such as 

 our own, hibernation is an attempt on the part of the 

 snake to avoid the extreme cold, when the natural 

 food is impossible of attainment and the general 

 environment such as no cold-blooded creature can 

 tolerate. Snakes are very susceptible to cold, even 



