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THE ZOOLOGIST. 



fat, and I was not a little astonished to see them one after 

 another, in the month of May, fall into their lethargic sleep, 

 which, according to all I had read in books, ought only to 

 have occurred in winter under the influence of cold. They 

 became as slothful as little bears — their movements got slower and 

 slower ; finally they squatted in a corner and became completely 

 lethargic. 



" In this condition their temperature became lowered, their 

 respiratory action became slower, and their lips presented an 

 ashy appearance. The little animals, placed in the open air, and 

 at first more or less rolled up, ended by remaining half extended 

 on their backs ; nevertheless on being pricked they made certain 

 reflex movements, especially a feeble grunting or whistling, and 

 by dint of exciting them I was able for a moment to instil a little 

 life into them. But as soon as I left them quiet they relapsed 

 into their lethargy. I then made a rather curious experiment : 

 I took one of the Dormice and placed it on the top of the little 

 fir tree in the middle of the cage. Although it was asleep it was 

 suflicient to make it touch a slender branch with the plantar 

 surface of its paws to excite a reflex contraction, which made it 

 grasp the branch which it would instinctively have done if awake. 

 I then let go, leaving him thus suspended to his branch. He 

 relapsed by degrees into somnolency. The muscles of the 

 grasping paw slowly relaxed, the plantar surface extended began 

 to hold the branch only at its extremity near the claws, and 

 I feared my Dormouse was going to fall ; but at the moment of 

 losing its equilibrium a sort of instinctive spasm shot through its 

 nervous system, and another paw seized the lower branch next 

 within reach in such a way that the animal only came down a peg. 

 Then the same performance was repeated. The Dormouse 

 relapsed into sleep at first, the foot slowly relaxed its hold up 

 to the moment of letting go, when the other paw caught hold of 

 a lower branch ; thus it descended, sleeping without falling, the 

 whole way down the fir tree from top to bottom, until it reached 

 the floor of the cage, where it remained in a state of lethargy. 

 I repeated the experiment several times with the two Dormice, 

 always with the same result ; neither of them ever allowed itself 

 to fall. 



" The sleep of these Dormice — occasionally interrupted by a 

 day or a few hours awakening, more or less complete, during 



