photo..1930s structual testing French?

Hi all,
Can anyone out there offer an I.D. or info to the attached photo, looks to be of 1930s vintage.
Structual testing of a wing, judging by the roundel a French type of some sort. Looks like ply-wood skinning, a one piece wing with a fair degree of dihedral, gun cut outs in L/E??

Cheers, Chumpy.

Interesting, however to me the roundel appears to have a outer ring which given the tonal value suggests it might be yellow and therefore probably post war.

But apart from that I can’t offer any other suggestions.