I posted this picture also in the thread on Napoleon III., but it fits also here.
This is Eleonore Vergeot, mistress of NIII, who gave him two sons, comte d'Orx and Comte de Labenne:
source: "Napoleon's children" by Susan Normington.
I found one more picture of her, on a site of a castle, where she had been, but the picture is too small. I wrote to the website and I'll see, if one can get it in a bigger version.