From Weird Tales, 1937

Madonna caught in an unguarded moment? No, it's Virgil Finlay's illustration for The Living Buddhess from the May 1937 issue of Weird Tales.

In the story which is one of Seabury Quinn's more than 80 stories featuring occult detective Jules de Grandin, a Buddhist lama in need of reincarnation decides to forgo the whole starting out as a baby route and instead takes over the body of a babe and refurbish for his needs.

This would be the first of Quinn's two gender change themed stories; the second one would be Alien Flesh which appeared in 1951. In that one a strapping young English explorer is turned into an Egyptian woman in payment for a debt.

Of note, Alien Flesh is the only Jules de Grandin adventure that was popular enough that it was `fleshed' out by Quinn from a novella to a full length novel and published in book form.

Madonna caught in an unguarded moment?

Are you sure on the date? ISFDB says it's actually the November 1937 issue:

http://www.isfdb.org/cgi-bin/pl.cgi?62094

I also can't find a reference to the 1951 version of Alien Flesh.

A quick search suggests that both the 1937 Weird Tales and the novel of Alien Flesh are, to put it mildly, not cheap even if you can find them. I think I own about 5 issues of Weird Tales, which is of course 5 more than most people...

The Living Buddhess appeared in 1937,

The Alien Flesh novel was ready in 1950, but may not have been published until 1977.

http://www.amazon.com/Alien-Flesh-Seabury-Quinn/dp/B0006CZLQA

I did a little further searching.

Alien Flesh doesn't seem to actually be a Jules de Grandin story, but a standalone work. It's an expansion of "Lynne Foster is Dead!" from the November 1938 issue of Weird Tales. And unlike the issue with "The Living Buddhess", this one is both a) in the public domain, and b) scanned for sharing. If anybody wants to read it, there's a link to it in various formats from this page.

http://www.pulpmags.org/weird_tales_page.html

It's an interesting read, in many ways it feels like it wouldn't be very much out of place on FM. Which is, of course, rather amazing for a story in a relatively mainstream magazine published in 1938!

That's a great find. Thanks for the research effort, it's much appreciated by duffuses like me who love to read old stuff that fits so nicely into this genre that we all crave.

Was poking around the internet a day or two ago and came across this:

http://pulpcovers.com/living-buddhess/#1

Has a link to the issue with the Living Buddhess story, for anybody who just has to see it. Short version: Unlike "Lynne Foster is Dead! / Alien Flesh", it's really not worth bothering with other than possibly the image Felix_Nine already shared and the beautiful Brundage cover. Still, there's always somebody (like me) who has to see for themselves, so the link is there. You'll need a CBZ/CBR reader to read it, or change the file type to .rar and unzip it to get to images of the pages.