One booklet that eluded this editor for the longest time is Sex in Inhibitia. I was finally able to obtain a copy Christmas 2016, with a number of other items.
The pamphlet itself is three pages long (the fourth page being blank), and at the end of the essay we see the statement “Reprinted from Haldeman-Julius Monthly,” a journal that is the source of his article turned pamphlet What is a Doodle-Goof?
I also found a useful note here: http://ead.lib.virginia.edu/vivaxtf/view?docId=uva-sc/viu00438.xml . It gives a rough overviews of letters between James Branch Cabell and Benjamin DeCasseres. Not only does it mention the essay, but gives us a reference date. Since DeCasseres had sent numerous letters prior to this one, including one in the same year, it’s plausible that “Sex in Inhibitia” was relatively new when the October 10th letter was written, and so we will place the date to that year, unless other proof comes about.
James Branch Cabell, Richmond, Virginia, to Benjamin De Casseres
1925 Oct 10 – TLS, 1 p.
expressing profound pleasure in reading Sex in Inhibitia