What is a stem pan?

I have a vintage cookbook, from Charlotte, North Carolina and about 1958, that has a recipe for “Different Applesauce Cake”. It says to “Cook in stem pan approximately 1 hour, 10 minutes”.

Searches for “stem pan” brings up pan definition lists that don’t include “stem pan”; searches for “stem pan baking” brings up a lot of pages on how to teach STEM using baking. There is one patent that appears at first to be about stem pans, but on reading seems to be about stems on pans. Though it could be that stem pan is another word for skillet.

In all cases, search engines like to replace “stem” with “steam”. There does appear to be something called a “steam pan”, but it appears to be the kind of pan used by buffet restaurants to keep food warm, not something for baking.

Searches on “stem pan” with “apple cake” do bring up some variations on some odd sites; but they don’t explain what it is. Some recipes use a variation of “use a loaf pan or a stem pan” and others a variation of “use a bundt pan or a stem pan”. Some suggest using it ungreased, some greasing and flouring the pan, others lining the bottom with greased paper, which seems a bit difficult if it’s just another word for bundt pan, or even if it’s another term for “tube pan” which is what I most suspect.

On the idea that this might be a dialect around Mississippi and North Carolina, I tried a search for “stem pan” and “southern” and found two contradictory recipe pages with images of the pan in question. A recipe for corn bread that has a photo of the corn bread in a skillet; this may be a stock photo, however. And a recipe for tomato soup cake that has a photo of it being poured into what looks like a bundt pan. So it may be that this is a term that applies to multiple items.

What is a stem pan? A skillet? A bundt pan? A tube pan? A loaf pan? A variation? Or something else? Or more than one item?