touching the forehead. Dr A. R. Wallace
remarks that "it is difficult to understand what can be the use of these
horn-like teeth. Some of the old writers supposed that they served as hooks
by which the creature could rest its head on a branch. But the way in which
they usually diverge just over and in front of the eye has suggested the
more probable idea, that they serve to guard these organs from thorns and
spines while hunting for fallen fruits among the tangled thickets of
rattans and other spiny plants. Even this, however, is not satisfactory,
for the female, who must seek her food in the same way, does not possess
them. I should be inclined to believe rather that these tusks were once
useful, and were then worn down as fast as they grew, but that changed
conditions of life have rendered them unnecessary, and they now develop
into a monstrous form, just as the incisors of the beaver and rabbit will
go on growing if the opposite teeth do not wear them away. In old animals
they reach an enormous size, and are generally broken off as if by
fighting." On this latter view we may regard the tusks of the male babirusa
as examples of redundant development, analogous to that of the single pair
of lower teeth in some of the beaked whales. Unlike ordinary wild pigs, the
babirusa produces uniformly coloured young. (See SWINE.)

(R. L.*)

BABOON (from the Fr. _babuin_, which is itself derived from _Babon_, the
Egyptian deity to whom it was sacred), properly the designation of the
long-muzzled, medium-tailed Egyptian monkey, scientifically known as _Papio
anubis_; in a wider sense applied to all the members of the genus _Papio_
(formerly known as _Cynocephalus_) now confined to Africa and Arabia,
although in past times extending into India. Baboons are for the most part
large terrestrial monkeys with short or medium-sized tails, and long naked
dog-like muzzles, in the truncated extremity of which are pierced the
nostrils. As a rule, they frequent barren rocky districts in large droves,
and are exceedingly fierce and dangerous to approach. They have large
cheek-pouches, large naked callosities, often brightly coloured, on the
buttocks, and short thick limbs, adapted rather to walking than to
climbing. Their diet includes practically everything eatable they can
capture or kill. The typical representative of the genus is the yellow
baboon (_P. cynocephalus_, or _babuin_), distinguished by its small size
and grooved muzzle, and rangi