The Descent of Man

and differs from the young of both sexes. But as
with some few birds it is the female which is
brighter coloured than the male, so with the
Rhesus monkey (Macacus rhesus), the female
has a large surface of naked skin round the tail,
of a brilliant carmine red, which, as I was assured
by the keepers in the Zoological Gardens,
periodically becomes even yet more vivid, and
her face also is pale red. On the other hand, in
the adult male and in the young of both sexes
(as I saw in the Gardens), neither the naked
skin at the posterior end of the body, nor the
face, shew a trace of red. It appears, however,
from some published accounts, that the male
does occasionally, or during certain seasons,
exhibit some traces of the red. Although he is
thus less ornamented than the female, yet in the
larger size of his body larger canine teeth, more
developed whiskers, more prominent superciliary
ridges, he follows the common rule of the
male excelling the female.