reasons,--into a wonderful sound-box, as big as an English walnut,
which gives to the adult voice a depth of pitch and a booming
resonance that is impossible to describe. The note produced is a
prolonged bass roar, in alternately rising and falling cadence,
and in reality comprising about three notes. It is the habit of
troops of red howlers to indulge in nocturnal concerts, wherein
four, five or six old males will pipe up and begin to howl in
unison. The great volume of uncanny sound thus produced goes
rolling through the still forest, far and wide; and to the white
explorer who lies in his grass hammock in pitchy darkness,
fighting off the mosquitoes and loneliness, and wondering from
whence tomorrow's meals will come, the moral effect is gruesome
and depressing.

In captivity the youthful howler habitually growls and grumbles in
a way that is highly amusing, and the absurd pitch of the deep
bass voice issuing from so small an animal is cause for wonder.

It is natural that we should look closely to the apes and monkeys
for language, both by voice and sign. In 1891 there was a flood of
talk on "the speech of monkeys," and it was not until about 1904
that the torrent stopped. At first the knowledge that monkeys can
and do communicate to a limited extent by vocal sounds was hailed
as a "discovery"; but unfortunately for science, nothing has been
proved beyond the long-known fact that primates of a given species
understand the meaning of the few sounds and cries to which their
kind give utterance.

Thus far I have never succeeded in teaching a chimpanzee or
orangutan to say even as much as "Oh" or "Ah." Nothing seems to be