My 2 cents worth:
I have "Negronne" from Northwoods/One Green World, and "Petit Negri" from a private collection (I don't know where it was obtained from). Go to my website: http://sites.google.com/site/kiwifruitsalad2/ and look at the page of Dark Colored Figs.
Both photos are of Breba crop Figs. The "Negronne" leaf shown was the most advanced leaf form but they usually more closely resemble the "Petit Negri" leaf shown. "Petit Negri" also routinely produces non-lobed leaves but "Negronne" rarely if ever does that.
Some say the two varieties are the same, but I disagree! Look at the meat color of the two photos. "Negronne" always has white meat heavily tinged with violet, and "Petit Negri" always has white meat lightly tinged with pink/red. "Negronne" tastes OK but "Petit Negri" is always flavorless and mealy textured, so I regard them as two different but very similar varieties. Just my opinion and only Genetic Fingerprinting will answer the question.
Happy Growing, kiwibob, Seattle