Kwa and the Ape People by Perley Poore Sheehan

FOR two days and two nights--off and on in the way of jungle travel, yet traveling steadily enough--Kwa had worked his way through the outer fastnesses of the Sango Lobango country. A maze of sharp pinnacles and deep clefts, all jungle covered; steaming from fires and waters in the depths of the earth. The earth was like a thing alive. The breath of it was moist and hot. The jungle was a smothering green blanket.

He was never alone. Buffalo and elephants, chimps and gorillas, a band of okapi; a changing cloud of lesser creatures; leopards--they ghosted in, they lingered, they ghosted away again.