Letters credit from Todd Klein via http://kleinletters.com/. Klein's work is noticeable on the phone The Atom is sitting on.
In three chapters, each ending in a partial page.
Earth-1 origin of Aquaman; substantially different from the previous version in More Fun Comics.
On inside back cover. Originally in July 1954 issues; reprinted in February 1965 issues, but not 80 Page Giant Magazine (DC, 1964 series) #8 (March 1965).