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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 wstivation, 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 uo cold-blooded creature can 
tolerate. Snakes are very susceptible to cold, even 
