3i6 THE BIOLOGY OF THE SEASONS 



tions to one another, or, indeed, of any one even sleep 

 by itself, that we must be content here to use the word 

 somewhat loosely when we say that Winter is to many 

 forms of life a sleep-bringer. 



The great hypnotist lifts his hands, and the sap stands 

 still in the tree, and the song is hushed in the bird's throat ; 

 he makes his passes, and growth ceases in bud and seed, in 

 cocoon and egg ; he breathes, and sleep falls upon marmot, 

 hamster, and hedgehog, upon tortoise, frog, and fish, 

 upon snail and insect ; he commands his voice is the 

 North Wind and the water stands in the running brooks, 

 and the very waves of the fiord are still. Even in our 

 own mild country, is not the freezing of a considerable 

 part of Loch Fyne upon record ? 



Apart from the state of latent life in which a paste- 

 eel, for instance, may lie neither actively living nor really 

 dead for fourteen long years, and seeds for several decennia, 

 though not since the days of the Pharaohs there is no 

 form of sleep so near to death as this to which the Wizard 

 of the North commands the true hibernators. Somnolence 

 penetrates to the deepest recesses of the creature's con- 

 stitution, as the expert histologist has shown us in his fine 

 study of the minute structural changes observed in the 

 cellular elements of the sleeping hedgehog. 



The heart of the hibernator beats feebly and somewhat 

 irregularly, the breathing movements are at long intervals 

 and very sluggish, the food-canal is empty, income is 

 (apart from oxygen) at zero, and expenditure is but little 

 more. The sleeper may be immersed in water for twenty 

 minutes, or subjected for some time to noxious gases, but 

 without apparent effect in either case. The fat, accumu- 

 lated in days of plenty, is slowly burnt away, sustaining 

 in some measure the animal heat. In the warm-blooded 

 mammal the normal power of keeping an approximately 



