114 M. Flourens on the effects of 



above one another, as if for the purpose of keeping up and 

 prolonging their heat. 



Tn this brief account of my observations on lethargy, I 

 shall only allude generally to the state and the external con- 

 dition of the hybernating animal, two points in which preced- 

 ing authors have left little to be done, and I shall hasten to the 

 consideration of their internal or organic conditions, — a point 

 which will probably long constitute the true difficulty of the 

 subject. I shall begin therefore with the examination of the 

 state of the animal, and of its manner of awakening. 



During lethargy the animal has an orbicular and regularly 

 bent position, the mouth being applied under the belly, the 

 hind feet being brought forward, and the fore-paws bent 

 against the breast, the ears lying on the sides of the head, the 

 eyes firmly closed, and the whole body collected into a ball, 

 with the tail rolled quite round the body. 



In this state the animal is cold. We may touch it gently 

 without its moving, but it moves if we pinch it strongly. If 

 the irritation continues, it awakes ; and what will give us an 

 idea of the singularity of the state from which it emerges, is 

 the difficulty with which it experiences in awakening. It be- 

 gins by opening its mouth violently, and keeps it a long time 

 open. Its sides then heave, the thorax at first remaining im- 

 moveable ; the thorax then partakes in the motion of the sides, 

 and the respiration commences. The animal cries, and has the 

 appearance of being choked. Its whole body trembles; it 

 opens its eyes ; but it does not at first see. At last the wak- 

 ing takes place ; it sees, hears, and recovers by degrees its heat 

 and its motions. 



There are two distinct degrees of lethargy ; in one, viz. im- 

 perfect lethargy we see the respiration suspended, and gradual- 

 ly resumed, every three, four, or five minutes, for example. 

 In the other, or perfect lethargy, the respiration is on the con- 

 trary completely extinguished, and I have often seen this ex- 

 tinction continue for whole hours during the continuance of 

 my observation. 



In imitation of Spallanzani, I submitted several torpid ani- 

 mals to the action of different mephitic gases, and though I 

 did not obtain exactly the same results as he did, it follows 



3 



