Well, MF was using at least between 1900 and 1930:
"bande a tenon d'accrochage s'encastrant dans la bascule"
or also
"loupe d'accrochage etc."
"Loupe" (magnifier) makes sense as it describes the shape of the doll's head as seen from the top.
"Tenon" would make sense for a Greener type, but was used either way.

This is quite a mouthful. I'll have to look at other catalogues. The Belgians have something different more than likely.
WC-