MAMMALS. 591 



together, as do the tusks of boars. Although wild boars 

 figlit desperately, they seldom, according to Brehm, receive 

 fatal wounds, as the blows fall on each other's tusks, or on 

 the layer of gristly skin covering the shoulder, called by 

 the German hunters the shield; and here we have a part 

 specially modified for defense. With boars in the prime 

 of life (fig. 65) the tusks in the lower jaw are used for 

 fighting, but they become in old age, as Brehm states, so 



Fig. 66. Skull of the Babirusa Pig (from Wallace's " Malay Archipelago"). 



much curved inward and upward over the snout that they 

 can no longer be used in this way. They may, however, 

 still serve, and even more effectively, as a means of defense. 

 In compensation for the loss of the lower tusks as weapons 

 of offense those in the upper jaw, which always project a 

 little laterally, increase in old age so much in length and 

 curve so much upward that they can be used for attack. 

 Nevertheless, an old boar is not so dangerous to man as 

 one at the age of six or seven years.* 



^ *5fPlwa, " Tbierleben," B. ii, ss. 729-73^. ' 



