HIBERNATION 



the happy hours away." Squirrels and dormice frequently 

 do so, as also some of the species of bats ; the warmth of 

 the day causing a few insects to put in an appearance, 

 upon which the bats feed for an hour or two, and again 

 quietly hide up before the temperature lowers sufficiently 

 to produce numbness. These, like the dormice and other 

 rodents, when in a torpid state, are, to the touch, if taken 

 into the hand, perfectly cold, and are quite motionless, and 

 to all appearance dead ; but upon the temperature being 

 raised, they become in a short time lively and active. 

 Were it necessary to enlarge by additional facts to show 

 that in a large number of cases temperature is sufficient 

 to account for the lethargy, a better case cannot be selected 

 than the common dormouse ; nothing more is required 

 to rouse this little pet from his slumber than to increase 

 the warmth of the apartment ; the animal will without 

 injury wake up and feed as often during the winter as is 

 thought proper ; endless experiments have been success- 

 fully tried to prove this. Let it, however, be borne in 

 mind that these animals to be experimented upon must be 

 perfectly healthy, and in the excessively fat state natural 

 to them before the winter sets in, otherwise they will not 

 live during the cold weather. Another important matter 

 is not to change the, temperature too rapidly, for few 

 animals can live or continue in good health if the tempera- 

 ture is suddenly and frequently changed by many degrees. 

 There can be no question that the animals that hibernate 

 are always excessively fat previous to retiring to sleep, for 

 if otherwise, they would die from the effects of the cold 

 and exhaustion ; it is equally certain that during the period 

 of hibernation this store of fat is being consumed by ab- 

 sorption, for at the termination of the winter those animals 

 that have slept all the cold season wake up quite thin and 

 hungry. 



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