Possibly apocryphal rumor has it that there used to be a couple of pickled pygmies in there, amongst other things, and that they were either secretly buried in the courtyard or given to the Mütter long ago.
But I don’t know of any pygmy corpses on display at the Mütter, and when the courtyard was dug up in the 90s the only really interesting bones found were a giraffe’s.
I once found a weird large yellow parchmenty thing in an extremely fancy stainless steel box full of alcohol. Nobody knew where it came from, so I went to each of the department heads with it on a little cart and said “is this yours, or do you at least know what it is?” When I got to the late Fred Ulmer in Mammalogy, he looked up calmly and said “Oh, that’s a hippopotamus stomach, we’ve been wondering where that got to.”