Chap. XIX. 
SEXUAL DIFFERENCES. 
319 
cranium of the adult male presents a strongly-marked 
sagittal crest, which is absent in the female ; and Ecker 
found a trace of a similar difference between the two 
sexes in the Australians . 8 With monkeys when there 
is any difference in the voice, that of the male is the 
'Lore powerful. We have seen that certain male mon- 
keys, have a well-developed heard, which is quite de- 
ficient, or much less developed in the female. No in- 
stance is known of the beard, whiskers, or moustache 
being larger in a female than in the male monkey. 
Even in the colour of the beard there is a curious 
parallelism between man and the Quadmmana, for 
"'hen in man the beard differs in colour from the hair 
°f the head, as is often the case, it is, I believe, in- 
variably of a lighter tint, being often reddish. I have 
observed this fact in England, and Dr. Hooker, who 
attended to this little point for me in Russia, found 
"o exception to the rule. In Calcutta, Mr. J. Scott, 
°f the Botanic Gardens, was so kind as to observe with 
c are the many races of men to be seen there, as well 
as in some other parts of India, namely, two races in 
Sikkim, the Bhoteas, Hindoos, Burmese, and Chinese. 
•Although most of these races have very little hair on 
fhe face, yet- he always found that when there was any 
difference in colour between the hair of the head and 
file beard, the latter was invariably of a lighter tint. Now 
"’itli monkeys, as has already been staled, the beard 
frequently differs in a striking manner in colour from 
fhe hair of the head, and in such cases it is invariably 
°f a lighter hue, being often pure white, sometimes 
yellow or reddish . 9 
8 ‘Anthropological Review,* Oct. 1858, p. 353. 
a Mr. Blyth informs me that he lms never seen more than one instance 
°f the beard, whiskers, &e., in a monkey becoming white with old age, 
as is so eommouly the case with us. This, however, occurred in an aged 
