One Panel #122-125: Zatara Meets the Manhunter from... Saturn?

From Zatara: "The Terror from Saturn" by Gardner Fox and Fred Guardineer, Action Comics #16 (September 1939)

Noooo, that's not the Martian Manhunter, but you gotta admit. The DCU DOES have a hero from Saturn, Jemm, but I guess Earth-2 has a different species hanging out on the ringed planet. Also, completely different physical properties.

From Jack Woods: "The Fiddler and the Bank Robbers: Part 2" by Jim Chambers, Adventure Comics #42 (September 1939)
Sandman is the only costumed hero in Adventure to date, so it's important to also pay respect to the other adventure genres featured in the book. Westerns, for example. I simply love this death pose, for example.

From Mutt & Jeff by Bud Fisher, All-American Comics #7 (October 1939)

Mutt & Jeff also scored their own book on this month in history, but I didn't manage access to it, so it's a good thing they were still appearing in All-American. Bud Fisher was far more than a humor strip cartoonist, as you can see from his wonderful drafting here.

From "Superman Champions Universal Peace!" by Jerry Siegel, Joe Shuster and Paul Cassidy, Superman #2 (September 1939)
The second issue of the quarterly Superman book features only one reprint, and it's of a newspaper strip that would not have appeared in Action Comics. Other firsts include the reveal that Clark Kent's editor at the Daily Star is named George Taylor, and Superman's first use of telescopic vision (in a TEXT story, of all places); it would not appear in a graphic story until Action #20.