Chap. XIX.] SEXUAL DIFFERENCES. 303 



negro child is reddish nut-brown, which soon "becomes 

 slaty-gray ; the black color being fully developed within 

 a year in the Soudan, but not until three years in Egypt. 

 The eyes of the negro are at first blue, and the hair chest- 

 nut-brown rather than black, being curled only at the ends. 

 The children of the Aiistralians immediately after birth 

 are yellowish-brown, and become dark at a later age. 

 Those of the Guaranys of Paraguay are whitish-yellow, 

 but they acquire in the course of a few weeks the yellow- 

 ish-brown tint of their parents. Similar observations have 

 been made in other parts of America.^ 



I have specified the foregoing familiar differences be- 

 tween the male and female sex in mankind, because they 

 are curiously the same as in the Quadrumana. With 

 these animals the female is mature at an earlier age than 

 the male ; at least this is certainly the case with the Cehus 

 azaroe.^ With most of the species the males are larger 

 and much stronger than the females, of which fact the 

 gorilla ofiers a well-known instance. Even in so trifling a 

 character as the greater prominence of the superciliary 

 ridge, the males of certain monkeys difier from the ■ fe- 

 males,^ and agree in this respect with mankind. In the 

 gorilla and certain other monkeys, the cranium of the 

 adult male presents a strongly-marked sagittal crest, which 

 is absent in the female ; and Ecker found a trace of a sim- 



^ Pruner-Bey, on negro infants, as quoted by Vogt, ' Lectures on 

 Man,' Eug. translat. 1864, p. 189 : for further facts on negro infants, as 

 quoted from Winterbottom and Camper, see Lawrence, ' Lectures on 

 Physiology,' etc. 1822, p. 451. For the infants of the Guaranys, see 

 Kengger, ' Siiugethiere,' etc. s. 3. See also Godron, ' De I'Espece,' torn. 

 ii. 1859, p. 253. For the Australians, Waitz, ' Introduct. to Anthropol- 

 ogy,' Eng. translat. 1863, p. 99. 



^ Rengger, 'Siiugethiere,' etc. 1830, s. 49. 



' As in Macaem cynomolgus (Desmarest, ' Mammalogie,' p. 65) and in 

 Hylohates agilis (GeoflFroy St.-Hilaire and F. Cuvier, 'Hist. Nat. des 

 Manun.' 1824, torn. 1. p. 2). 



