The Descent of Man

transmitted equally, or almost equally, to both
sexes. With many of the Quadrumana, we have
additional evidence of the action of sexual selection
in the greater size and strength of the
males, and in the greater development of their
canine teeth, in comparison with the females.
[Fig. 77. Cercopithecus petaurista (from
Brehm).]
A few instances will suffice of the strange manner
in which both sexes of some species are
coloured, and of the beauty of others. The face
of the Cercopithecus petaurista (Fig. 77) is
black, the whiskers and beard being white,
with a defined, round, white spot on the nose,
covered with short white hair, which gives to
the animal an almost ludicrous aspect. The
Semnopithecus frontatus likewise has a blackish
face with a long black beard, and a large
naked spot on the forehead of a bluish-white
colour. The face of Macacus lasiotus is dirty
flesh-coloured, with a defined red spot on each