WING OP THE BAT. 15 



In speaking of the bat, I have used popular terms, 

 and therefore have employed the word " wing ". 

 But the apparatus of the bat is not a wing at all, but 

 only a developed hand. Let the reader spread his 

 hand as wide as he can, and he will see that between 

 each finger, and especially between the forefinger 

 and the thumb, the skin forms a kind of webbing, 

 something of the same kind as that on the feet of 

 ducks and other aquatic birds. 



Now if the bones of the fingers were drawn out 

 like wire until they became some seven or eight feet 

 long, and the skin between them were extended to 

 the nails of the elongated fingers, we should have a 

 structure analogous to that of the bat's wing. The 

 thumb joint is left comparatively free ; and by means 

 of this joint, and the hooked claw at its extremity, 

 the creature walks on a level surface, or can crawl 

 suspended from a beam or a trunk. It is very curi- 

 ous to see the bat stretching out its wings and feel- 

 ing about for a convenient spot whereon to fix the 

 hooks. 



So tenacious are these hooks, that the baby bat is 

 often found enjoying an airing by clinging to the 

 body of its mother, and holding firm, while she flies 

 in search of prey. 



It is true that the little creature is suspended with 

 its head downwards ; but it appears quite comfort- 

 able, nevertheless. Bat-children do not suffer from 

 determination of the blood to the brain. Neither do 



