5° 



TEXT-BOOK OF ZOOLOGY 



about 6 feet in length, opening below the surface of the water. Another 

 passage leading to the edge of the bank effects the ventilation of the 

 chamber. 



Family 5 : Bears (Ursidae), 



1. The Brown Bear (Ursus arctos). 



(Length about 6J feet ; height at shoulders up to about 4 feet.) 



A. Structure and Mode of Life. 

 The bear is at once a flesh and vegetable eater. An examination of its 

 anatomy will explain to us this double nature : 



1. The body is stout. 



2. It treads on the whole surface of its naked soles (plantigrade). It 

 cannot accordingly run as fast as those carnivores which walk on their 



toes — Digitigrades (compare the wolf). Nor 

 is it able to glide about or leap as nimbly as 

 several of the latter. Still, its motions are 

 not so slow as one might suppose, and it can 

 easily outstrip a man in speed. 



3. To some extent it makes up for its 

 want of rapidity by the great mobility of its 

 limbs and enormous corporal strength. Being 

 able to walk on its hind-limbs, it can keep its 

 fore-limbs free. It uses these like arms, and 

 by embracing its victims, either men or cattle, 

 breaks all their ribs. The hind-legs being 

 much longer than the fore-legs, it can run 

 more quickly uphill than downhill (compare 

 with the hare). It can fell a man to the 

 ground or break the backbone of a sheep or 

 goat with one blow of its powerful paws, and 

 when proceeding on its hind-limbs is even 

 capable of carrying off an ox in its arms. 

 The bear is a skilful climber in virtue of its great strength, the 

 mobility of its limbs, and the long, strong claws, which, however, are not 

 retractile. It ascends with ease lofty trees and steep rocks. When in 

 pursuit of cattle it first tries to frighten the beasts by setting up a terrible 

 roar, and then drives them down into a ravine or chasm, which next it 

 descends itself with great agility. It is also an excellent swimmer. 



4. Though the ears are small, the sense of hearing is very fine, and the 

 same may be said in regard to the sense of smell. It can hear the least 



3. 2. 1. M. 



FOEE-LEG OF BEAK. 



0., Humerus; Sp., radius; E. 

 ulna ; Hw., carpal bones 

 M., metacarpals ; 1, 2, 3 

 phalanges. 



