THE BAT. 177 



length that the body of the creature will pass through 

 any opening which these hairs do not touch on either 

 side. They are very sensitive ; and, if ever so lightly 

 touched, the animal is instantly aware of it, even while 

 asleep. Horses have strong hairs both on the upper 

 and lower lips, but they are probably designed to keep 

 flies and insects from annoying them by getting into 

 their nostrils while grazing. Sufficiently close for this 

 purpose, and moving as they do, while the horse is 

 feeding, they serve to brush away anything offensive. 



To return now to the bat : the extremities afford the 

 means of walking on the ground, and of climbing easily 

 up perpendicular places, if there are sufficient inequalities 

 on the surface to allow of a firm hold by the little hooked 

 nail of the thumb. In walking, the wings are closed, 

 the long fingers being folded against the arm, and the 

 animal rests upon the wrist. The foot of one side is 

 then stretched forward, and the thumb-nail is hooked 

 into the ground ; the body is next raised by means of 

 the hinder foot, which has been placed partly under the 

 body, and thus thrown onward ; the other side is next 

 moved in the same manner, and by a succession of 

 these plunges the animal runs, oddly, compared with 

 other animals, but in a manner sufficient for its wants. 



During the day, bats sleep in the most retired places, 



