Experiments on Bats deprived of S'igll. 137 



four, and unequal. The horfe-fnoe bat has none in the up- 

 per jaw, except two fmall ones in the membrane of the pa- 

 late: the lower jaw is furnifhed with four. When the horfe- 

 ihoe bat attaches itfelf to a wall, it contracts its body, and 

 wraps itfelf up in its fur in fuch a manner that it might be. 

 taken for a black ctiryfalide. The long-eared bat appears 

 Ids careful of itfelf, and firll makes ufe of its hind feet, and 

 then of thofe before, in order to affix itfelf to a walk 



The temperature of the vaults which ferved them for a 

 habitation was between 50" and 57" Fahr. that of the exter- 

 nal air between 27° and 30^. M. Jurine having cxpofed fome 

 of thefe animals to a temperature between 36° and 39°, 

 feveral of them perifhed, and others fell into a ftate of tor- 

 pidity ; from which he was not able to roufe them by any 

 touching, though a gentle current of air directed againft 

 them caufed them to make a movement, by drawing back 

 the whole body on the hind legs, and this they repeated as 

 often as the infufflation was renewed. M. Jurine had before 

 obferved the fame effect on mice. He remarked, however, 

 that the approach of a candle agitated and awakened them, 

 probably on account of the rarefaction of the ambient air. 

 A violent agitation of the air by which they are furrounded 

 makes them fpeedihy take wing. 



During the torpid ftate of thefe animals no movement 

 is obferved which can indicate that they breathe. A fmall 

 horfe-fhoc bat, a large bat of the fame fpeeics, and a 

 lono--eared bat were placed on a Move, and exhibited 

 figns of life at different periods; but their infpiration 

 and expiration were extremely irregular, particularly thofe. 

 of the long-eared bat. There, is a ftriking difference be- 

 tween the pofition of thefe two fpecies of bats when they fix 

 thcmfelves againft any object. The horfe-flioe bat hooks it- 

 felf all at once, with its head down and its legs upwards ; 

 while the long-eared bat turns itfelf round quietly, in order 

 ^0 affumc very often an oblique pofition. 



The 



