The grand plans for the Ellery Queen Selects series began in 1947. Jonathan Press J26, Stuart Palmer’s “The Riddles of Hildegarde Withers,” was numerically the second in the series.
The excerpt from Frederic Dannay’s introduction to J26 below refers to “First Edition Mysteries.” This was apparently an inside, working title, as the digests replaced it with “Ellery Queen Selects” displayed across the top of the covers.
“[W]e preserve in our noble experiment, our colossal publishing venture, and bring you the next in our series [starting with the Hammett collections] of First Edition Mysteries—“The Riddles Of Hildegarde Withers” by Stuart Palmer. Coming soon—watch for them!—will be John Dickson Carr’s never-previously-published book of short stories titled “Dr. Fell, Detective and Other Stories;” Roy Vickers’s never-previously-published “The Department Of Dead Ends;” and Margery Allingham’s “The Case Book Of Mr. Campion;” and unquestionably there will be additional First Edition Mysteries to follow.”