£. ANIMALCULA OF INFUSIONS. 85 



Whence does it happen that ahnoft all reptiles 

 and ail infefts, at a certain degree of cold, lofe 

 their whole vigour j their motion ceafes, and 

 they affume the appearance of death ; while 

 man, and the moft part of quadrupeds and birds, 

 at an infinitely greater degree, retain their ori- 

 ginal flrength and vivacity ? What can be the 

 proximate, the immediate caufe of this apparent 

 death in the former animals, and that it is not fo 

 in the latter ? No one that I know of, before 

 M. de BufFon, fet himfelf feriouily to confider 

 this fingular phenomenon. According to him, 

 the animals that become torpid are cold blooded. 

 Such had he found the greater dormoufe ( i ), 

 the common dormoufe, land hedgehogs, and 

 bats, which of themfelves have no internal 

 heat, and only that of the atmofphere. Their 

 blood refrigerates in proportion as the atmofphere 

 refrigerates, which cannot take place with warm 

 blooded animals from their internal principle of 

 heat. Torpidity mufl enfue from this refrigera- 

 tion, becaufe the ufe of the fenfes and limbs is 

 F 3 loft 5 



ly revived on removal to a milder atmofphere. Some, 

 however, preferved a languid motion while the water was 

 about 32°. La Cepede appears to confider fillies, in gene- 

 ral, fubjeft to a degree of torpor ; and he fays, the deeper 

 the lethargy, the lefs of their fnbftance is loft. — Hijloirs. 

 des Poijons, T. i. Difcours, p. 132. i?^.— -T. 

 (1) By him called Lerots. 



