DC · May, 1964
Keys of Knowledge: Medicine #6: Roman and Medieval Medicine (illustrated text); Captive of the Vulture; Jungle Greenhouse (text); The Lonely Hut (Jon of the Kalahari); Warrior’s Test; Keys of Knowledge: Wild Animals of South America #14: Guinea Pigs (illustrated text)
Writer: Gaylord Du Bois
Artists: Russ Manning, Jesse Marsh