Mr. Mxyztplk first appeared in Superman #30.
The story takes place in a city setting, not the jungle.
Letterer credit added by Craig Delich.
Script credit added by Craig Delich.
Second page in inside back cover.
Art credits by Jerry Bails. Alvin Schwartz script credit removed by Craig Delich. According to the Who's Who, Schwartz wrote this strip from 1946-48.