Sunday is Monkey Covers day here at YACB. Because there's nothing better than a comic with a monkey on the cover!
No mad scientist's laboratory is complete without a menacing gorilla, as seen on Henry Scarpelli's cover to Abbot and Costello #2 (1968).
(Standard disclaimer about lab-dwelling gorillas not really being monkeys applies.)
Image courtesy of the GCD. Click on the image for a larger version.