Ah, now it begins to make sense. Jules Gastambide died in 1922, but Robert Gastambide was his son and must have teamed up with Levavasseur again for this monstrosity. Hard to believe that the creator of the beautiful Antoinette could come up with this, though. The VG wing probably explains that 'fence like' device, maybe a guide for the sliding sections. The French were into VG in the 1920s. The Makhonine mentioned in the pervious post actually had a telecopic wing whose span could be varied.