It turns out they were called "Pop-over Pans" and they really aren't very old. The pan on the right is an actual Griswold. It was cast in Erie PA probably in the 1950s. The pan on the left has the markings of both Wagner Ware and Griswold so it was produced after the Wagner Mfg. Co. acquired Griswold in 1957. It was made using the same pattern, but was cast in Sidney OH in either the 1960s or early 1970s.
As you can see the Griswold is a much nicer casting than the later Wagner made piece.
Interior of the Wagner produced pan.
Interior of the actual Griswold.
I think this post is a good illustration of why cast iron collectors regard the 1960s as a turning point. The quality of the cast iron produced before the sixties was simply better.