From memory it has neither. M&G used Gurtner carbs on their two-strokes at that time. Somewhere I have a specifications list for all Monet et Goyon bikes and I can remember noting M&G in the 1930's using the Gurtner on their two-strokes and Amac on their four-strokes.
It was notable because the early 1930's was the time M&G were slowly moving from importing Villiers engines to making them under licence and of course using Amac on their four strokes was curious as well. How come? Amac had combined with B&B and Binks to become Amal carbs in 1928. What was an Amac carb doing on a French make years later? Were they also made under licence in France?
I'll hunt around for my M& G file and let you know but meanwhile I'd go for Gurtner.
Cheers,