First B'wana Beast. In Amazing World of DC Comics #10, January 1976, in the article "There's No Cases Like Showcases", Jack C. Harris notes, "George Kashdan made his SHOWCASE editorial debut and farewell with a two-issue origin of Mike Sekowsky's jungle hero B'wana Beast in #66 (Jan./Feb. 1967) and #67 (Mar./Apr. 1967). Only a third-rate Tarzan, Mike Maxwell's alter-ego was lost on the newsstands."
"B'wana Beast! The Jungle Master" is how the name is rendered on the cover and first page.
1) Script credit from Kurt Mitchell. 2) But the Amazing World of DC Comics article calls it "Mike Sekowsky's B'wana Beast", so Sekowsky may have authored. 3) Story continues next issue.
The title is a pun on wildly popular TV show The Man from U.N.C.L.E.