Sunday is Monkey Covers day here at YACB. Because there's nothing better than a comic with a monkey on the cover.
Tarzan rescues Boy from strange apes in The Caverns of Kor on the 1961 cover of Tarzan #129, painted by George Wilson.
(Standard disclaimer about rock- and club-wielding apes not really being monkeys applies.)
Image courtesy of the GCD. Click on the image for a larger version.