Chap. XVIII. VOCAL ORGANS. 275 



P, Egertoii, it seems that young stags under three 

 years old do not roar or bellow ; and tliat the old ones 

 begin bellowing at the commencement of the breeding- 

 season, at first only occasionally and moderately, whilst 

 they restlessly wander about in search of the females. 

 Their battles are prefaced by loud and prolonged hel- 

 lo wini2:, but durino: the actual conflict thev are silent. 

 Animals of all kinds which habitually use their voices, 

 utter various noises under any strong emotion, as when 

 enraged and preparing to fight ; but this may merely 

 be the result of their nervous excitement, which leads 

 to the spasmodic contraction of almost all the muscles of 

 the body, as when a man grinds his teeth and clenches 

 his hands in rage or agony. No doubt stags challenge 

 each other to mortal combat by bellowing ; but it is 

 not likelv that this habit could have led throu2;h 

 sexual selection, that is bv the loudest- voiced males 

 having: been the most successful in their conflicts, to 

 the periodical enlargement of the vocal organs ; for the 

 stags with tlie most powerful voices, unless at the same 

 time the strongest, best-armed, and most courageous, 

 would not have gained any advantage over their rivals 

 with weaker voices. The stags, moreover, which had 

 weaker voices, though not so well able to challenge other 

 stags, would have been drawn to the place of combat as 

 certainly as those with stronger voices. 



It is possible that the roaring of the lion may be 

 of some actual service to him in striking terror into 

 his adversary ; for when enraged hfe likewise erects his 

 mane and thus instinctively tries to make himself ap- 

 pear as terrible as possible. But it can hardly be sup- 

 posed that the bellowing of the stag, even if it be of 

 any service to him in this way, can have been im- 

 portant enough to have led to the periodical enlarge- 

 ment of the throat. Some writers su[>o:est that the 



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