The Humorist was another of the Newnes publications to which Wodehouse contributed; from available evidence, this one seems to have been a weekly pulp tabloid, with only black-and-white illustrations and text inside a color cover. It was founded in 1922, and merged with London Opinion about 1940.
Thanks to Visual Rants for information and the cover scan (from 1928) shown above. More data at Magforum.