40 NATURAL HISTORY. 
gers enormously lengthened. Ifthe 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, 1s 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.— 
age The bats in no case 
Fig ot) “tong eared Bate flew against them, but 
