5i8 



The Descent of Man. 



Part II- 



The males of some few quadrupeds possess organs or parts 

 developed solely as a means of defence against the attacks of 

 other males. Some kinds of deer use, as we have seen, the 

 upper branches of their horns chiefly or exclusively for de- 

 fending themselves ; and the Oryx antelope, as I am informed 

 by Mr. Bartlett, fences most skilfully with his long, gently 

 curved horns; but these are likewise used as organs of offence. 

 The same observer remarks that rhinoceroses in fighting, parry 

 each other's sidelong blows with their horns, which clatter 

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

 fight 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 spe- 

 cially modified for defence. 

 With boars in the prime 

 of life (see fig. 65) the 

 tusks in the lower jaw are 

 used for fighting, but they 

 become in old age, as 

 Brehm states, so much 

 curved inwards and up- 

 wards over the snout, 

 that they 'can no longer 

 be ufed in this way. 

 They may, however, still 

 serve, and even more 

 effectively, as a means 

 of defence. In compensation for the loss of the lower tusks 

 as weapons of offence, those in the upper jaw, which always 

 project a little laterally, increase in old age so much in length 

 and curve so much upwards, 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. 39 



In the full-grown male Baburisa pig of Celebes (fig. 66), the 

 lower tusks are formidable weapons, like those of the European 

 boar in the prime of life, whilst the upper tusks are so long 

 and have their points so much curled inwards, sometimes even 

 touching the forehead, that they are utterly useless as weapons 

 of attack. They more nearly resemble horns than teeih, and 

 are so manifestly useless as teeth, that the animal was formerly 

 supposed to rest his head by hooking them on to a branch! 

 Their convex surfaces, however, if the head were held a little 

 39 Brehm, < Thierleben,' B. ii. s. 729-732. 



Fig. 63 



Head of Common wild hoar, in prime 

 of life (from Brehm). 



