5*4 



The Descent of Man. 



Part II. 



tiger to the ground and, in consequence, is dangerous to the 

 rider, who is liable to be jerked off the howdah. 30 



Very few male quadrupeds possess weapons of two distinct 

 kinds specially adapted for fighting with rival males. The male 

 muntjac-deer (Cervulus), however, offers an exception, as he is 

 provided with horns and exserted canine teeth. But we may 

 infer from what follows that one form of weapon has often 

 been replaced in the course of ages by another. With ruminants 

 the development of horns generally stands in an inverse relation 

 with that of even moderately developed canine teeth. Thus 

 camels, guanacoes, chevrotains, and musk-deer, are hornless, 

 and they have efficient canines; these teeth being "always of 

 " smaller size in the females than in the males." The Camelidae 

 have, in addition to their true canines, a pair of canine-shaped 

 incisors in their upper jaws. 31 Male deer and antelopes, on the 

 other hand, possess horns, and they rarely have canine teeth; 

 and these, when present, are always of small size, so that it is 

 doubtful whether they are of any service in their battles. In 

 Antilope montana they exist only as rudiments in the young 

 male, disappearing as he grows old ; and they are absent in the 

 female at all ages ; but the females of certain other antelopes 

 and of certain deer have been known occasionally to exhibit 

 rudiments of these teeth. 32 Stallions have small canine teeth, 

 which are either quite absent or rudimentary in the mare; but 

 they do not appear to be used in fighting, for stallions bite 

 with their incisors, and do not open their mouths wide like 

 camels and guanacoes. Whenever the adult male possesses 

 canines, now inefficient, whilst the female has either none or 

 mere rudiments, we may conclude that the early male pro- 

 genitor of the species was provided with efficient canines, which 

 have been partially transferred to the females. The reduction of 

 these teeth in the males seems to have followed from some 

 change in their manner of fighting, often (but not in the horse) 

 caused by the development of new weapons. 



Tusks and horns are manifestly of high importance to their 



** Sjs "iso Corse (' Philosoph. 

 Transact. 1799, p. 212) on the 

 jnanner in which the shovt-tusked 

 Mooknah variety attacks other ele- 

 phants. 



31 Owen, 'Anatomy of Verte- 

 Vrstes, 5 vol. iii. p. 349. 



* 2 See Riippell (in ' Proc. Zoolog. 

 Soc.' Jan. 12, 1836, p. 3) on the 

 canines in deer and antelopes, with 

 a note by Mr. Martin on a iemale 



American deer. See also Falconer 

 (' Pala?ont. Memoirs and Notes/ 

 vol. i. 1868, p. 576) on canines it. 

 an adult female deer. In old males 

 of the musk-deer the canines (Pallas, 

 ' Spic. Zoolog.' fasc. xiii. 1779, p. 

 18) sometimes grow to the length 

 of three inches, whilst in old females 

 a ndiment projects scarcelv hall 

 an inch ;ibove thr; gums. 



