Which gender did Matisse and Picasso most often paint in their younger years ?
" ' Among Pablo Picasso 's acquaintances who also frequented the Saturday evenings were : Fernande Olivier ( Picasso 's mistress ) , Georges Braque , André Derain , the poets Max Jacob and Guillaume Apollinaire , Marie Laurencin ( Apollinaire 's mistress and an artist in her own right ) , and Henri Rousseau .