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TEXT-BOOK OF ZOOLOGY 



able nimbleness, and by help of the tail, which acts as a rudder, can even 

 execute rapid turns. 



ii. How Bats creep and climb. 



The bat, however, cannot be said to be an aerial creature in the same 

 degree that the fish is spoken of as an aquatic animal. In order to rest 

 it is obliged to descend upon solid objects. The limbs, accordingly, are 

 not merely instruments for flying, but also for creeping and climbing 

 (compare with seal). 



1. By means of its claw-shaped thumb, it hooks itself on to the 

 ground, and then pushes its body forward with its feet. (Would this 



be possible if thumb and feet were in- 

 cluded in the flying membrane?) In 

 this manner the bat creeps, though 

 somewhat awkwardly. 



2. On account of the shortness and 

 weakness of its legs, the bat cannot 

 dart upwards into the air in the manner 

 of a bird, nor is it able to unfold the 

 flying membrane to its fullest extent 

 while still on the ground, since the legs 

 are to some extent enclosed within it. 

 For this reason it climbs up tree-trunks, 

 walls, or other objects, by the help of its 

 claw-like thumb and its feet, and then, 

 by allowing itself to drop, is once more 

 enabled to launch itself into the air. 



3. For the same reason the bat 

 BAT IN SUSPENDED assumes a peculiar position even when 



at rest, suspending itself by the feet, 

 head downwards, from projecting beams 



or edges of its dwelling-place. If while in this position it allows itself 

 to drop, it can at once expand its flying membrane. In spite of their 

 extreme slenderness, the feet are yet able to maintain the animal in 

 this suspended position during the day and the period of hibernation 

 (see below). 



B. Structure of Body and Food. 



The bat passes the day asleep, only making its appearance at sunset 

 for the nightly pursuit of its prey. This latter consists of flies, gnats, 

 beetles, and more especially moths. The bat, accordingly, is a nocturnal 

 insectivorous creature, and its structure is admirably adapted to these 

 habits. 



POSITION. (Natural size.) 



