SEXUAL SELECTION. 213 



males. In South America the Myoetes caraya presents well- 

 marked sexual differences, in color, beard, and vocal organs; and 

 the male generally lives with two or three wives: the male of the 

 Cebus capucinus differs somewhat from the female, and appears 

 to be polygamous.^" Little is known on this head with respect 

 to most other monkeys, but some species are strictly monoga- 

 mous. The ruminants are eminently polygamous, and they pre- 

 sent sexual differences more frequently than almost any other 

 group of mammals; this holds good, especially in their weapons, 

 but also in other characters. Most deer, cattle, and sheep are 

 polygamous; as are most antelopes, though some are monoga- 

 mous. Sir Andrew Smith, in speaking of the antelopes 

 of South Africa, says that in herds of about a dozen there was 

 rarely more than one mature male. The Asiatic Antilope saiga 

 appears to be the most inordinate polygamist in the world; for 

 Pallas" states that the male drives away all rivals, and collects a 

 herd of about a hundred females and kids together; the female 

 is hornless and has softer hair, but does not otherwise differ much 

 from the male. The wild horse of the Falkland Islands and of 

 the Western States of North America is polygamous, but, except 

 in his greater size and in the proportions of his body, differs but 

 little from the mare. The wild boar presents well-marked sexual 

 characters, in his great tusks and some other points. In Europe 

 and in India he leads a solitary life, except during the breeding- 

 season; but as is believed by Sir W. Elliot, who has had many 

 opportunities in India of observing this animal, he consorts at 

 this season with several females. Whether this holds good in 

 Europe is doubtful, but is is supported by some evidence. The 

 adult male Indian elephant, like the boar, passes much of his 

 time in solitude; but as Dr. Campbell states, when with others, 

 "it is rare to find more than one male with a whole herd of fe- 

 "males;" the larger males expelling or killing the smaller and 

 weaker ones. The male differs from the female in his immense 

 tusks, greater size, strength, and endurance; so great is the dif- 

 ference in these respects, that the males when caught are valued 

 at one-fifth more than the females." The sexes of other pachy- 



" On the Gorilla, Savage and Wyman. 'Boston Journal of Nat. Hist." 

 vol. V. 1845-47, p. 423. On Cynocephalus, Brehm, 'lUust. Thierleben,' 

 B. i. 1864, s. 77. On Mycetes, Rengger, 'Naturgesch. : Saugethiere 

 von Paraguay,' 18S0, s. 14, 20. Cebus, Brehm, Ibid. s. 108. 



"' Pallas, 'Spicilegia Zoolog.,' Paso. xii. 1777, p. 29. Sir Andrew 

 Smith, 'Illustrations of the Zoology of S. Africa,' 1849, pi. 29, on the 

 Kobus. Owen, in his 'Anatomy of "Vertebrates' (vol. iii. 1868, p. 633) 

 gives a table showing incidentally which species of antelopes are gre- 

 garious. 



" Dr. Campbell, in 'Proc. Zoolog. Soc' 1869, p. 138. See also an in- 

 teresting paper, by Lieut. Johnstone, in 'Proc. Asiatic Soc. of Ben- 

 gal,' May, 1868. 

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