The following images are from The Three Stooges' Micro-Phonies (1945). It is one of their better efforts, I would say. Highly recommended. Anyway, Moe is faux-playing to the sound of a recording of a silver flute, but he is "playing" a simple system flute, Meyer-style, with a B-foot and nine keys (maybe more, but I can't see). He has a charming way of putting his right hand fingers on the cups of the foot joint keys, rather than on the finger holes!
Why is he playing a nine-key flute? I originally thought that since the silver flute player was surely not going to lend this klutz his flute, an instrument was requested from the prop department, and that's what came back. The old flutes were still around in profusion in 1945.
But filmmaker Kevin Burget wrote to suggest the possibility that a black flute was chosen because it was non-reflective; a silver flute might have wrought havoc with the lighting. That does makes sense, and one could even imagine that a flute with fewer keys might be prefered. I don't know.