Unpublished 1973 Gil Kane Cover
The first four issues of Marvel's 1970s Jungle Action series presented reprints from 1950s Atlas comics featuring, among others, Jann of the Jungle. It was with this editorial direction that Gil Kane drew the cover shown above that was planned for the fifth issue.
A last-minute decision was made to modernize the title a bit and have it become a showcase for The Black Panther, and a different cover for Jungle Action #5 was drawn by John Romita (shown below).
Before today I had never seen the very nice Gil Kane drawing and, as of this writing, the original artwork is available for sale over here.