40 NATURAL HISTOET. 



gers enormously lengthened. If the bones of the fingers 

 of man were lengthened as much in proportion to his 

 size, his fingers would be about four feet long. What 

 answers to a thumb in the bat is a short projection with 

 a hook upon it, as you see in the figure. Wood says of 

 this arrangement that, " if the fingers of a man were to 

 be drawn out like wire to about four feet in length, a 

 thin membrane to extend from finger to finger, and an- 

 other membrane to fall from the little finger to the an- 

 kles, he would make a very tolerable bat." He would 

 need, however, vastly larger muscles than those which 

 move his arm to work such extensive flying machinery. 



59. The wing of a bat is a more extensive and perfect 

 flying apparatus than that of any bird. Hence the ex- 

 ceeding rapidity of its movements. In his flight he is 

 catching flies, musquitoes, and other insects. In his mode 

 of getting a livelihood he is like the birds of the swallow 

 tribe. 



60. The eyes of the bat are small, and his vision is un- 

 doubtedly very poor. How, then, can he catch insects 

 on the wing ? It is because his other senses are very 

 acute. He hears quickly. Especially is this the case 

 with the Long-eared Bat, Fig. 21. The organ of smell, 

 too, is quite extensive, particularly in some species. 

 Then, too, the membrane of the wings is fully supplied 



with nerves, and is 

 exquisitely sensitive. 

 To prove this, Spal- 

 lanzani put out the 

 eyes of some bats, 

 and then let them 

 loose in his room, 

 across which he had 

 stretched strings in 

 various directions. — ' 

 _ The bats in no case 



Fig. 21 Long-eared Bat. flew against them,but 



