158 THE STORY OF THE BIRDS 



at the approach of winter, and passed that sea- 

 son snugly hidden away in nooks and crannies, 

 or buried in the mud at the bottom of pools 

 of water. As most readers may know, Gilbert 

 White believed in this hibernation habit, and 

 not a few scientific men of distinction supported 

 the theory. Possibly opinion nowadays may 

 have gone too far in the opposite direction, and 

 the general ridicule with which suggested hiber- 

 nation among birds is received conceals the 

 actual facts. We must remember that seasonal 

 torpidity is a common practice among many 

 animals and insects ; that it is not a physical 

 impossibility in birds, although there can be 

 little doubt that if birds ever do sink into 

 lethargic slumber the isolated instances must 

 be exceedingly exceptional. There is some 

 evidence to suggest that birds have been known 

 to pass into this state. The testimony seems to 

 be absolute and reliable. On the other hand the 

 reader may rest assured that in no known species 

 does hibernation generally take the place of 

 migration. We have already dwelt at some 

 length upon this question of avine hibernation 

 in our book on the migration of birds, to which 

 the reader may be referred.^ Another equally 



^ The Aligration of Birds ^ chap, ii., pp. 50-69. 



