THE HAIR AND FUR OF ANIMALS. 151 



cation with the body of the animal, unless the per- 

 spirable matter is conducted alternately from side 

 to side along the bars. The fur of the bat, Fig. B, 

 has knots like the rudiments of branches. The 

 hairs of the hamster mouse, Fig. C, have a central 

 perforation, apparently uninterrupted throughout 

 their whole length. Some of the caterpillars 

 (callimorpha caja) have spines proceeding from the 

 hair that invests their bodies^ Fig. D*. All these^ 

 and the other various contrivances so manifest in 

 the coverings of animals, are probably designed to 

 convey off the perspirable fluids conducive to health 

 in an appropriate manner ; to discharge the super- 

 abundant heat, and keep the body temperate in 

 some cases ; in others, again, to retard perspiration, 

 and thus augment the warmth, by every possible 

 gradation, or to increase the sensibility and percep- 

 tions of the animal. Many instances of these 

 effects and modifications might be advanced, de- 

 serving a more extensive consideration. 



The smell of the flesh of the mole is remarkably 

 rank and offensive, as, from the nature of its food, 

 might be expected ; and it taints the fingers, which 



* The organ, which inflicts the pain, or sting, when we in- 

 cautiously handle the nettle, is well "known to be connected with a 

 little vessel containing an acrid fluid, which being compressed, 

 rushes up the tube of the organ, and is thus conveyed into the 

 wound ; and it is rather singular, that the larvae of the admirable 

 butterfly, which feeds upon the large hedge nettle, has the spines 

 which arise from its body branched, and each collateral hair arises 

 from a little bulb, similar to that of the plant on which it is chiefly- 

 found. 



