Giant snakes, poisonous serpents, reptiles of the slithering variety, all grace the covers of the comics. Two big sources are Tarzan and Conan covers. If you are going to live in the jungle or the ancient Hyborian Age you better be ready for snakes. Images from my youth go back to two classic snake covers for these characters, one by Frank Frazetta and another by Boris Vallejo. These artists had plenty of inspiration from the comics.
