Some of the greatest hits in art history are coming to Sotheby 's and Christie 's in Manhattan this weekend : a van Gogh portrait of Madame Ginoux , the proprietress of the Cafe de la Gare in Arles , France , which the artist frequented until his suicide in 1890 ; a 1941 Picasso painting of his mistress Dora Maar with a black cat perched on her shoulder , not publicly seen for more than 40 years ; and a haunting 1902 Blue Period Picasso of Germaine , one of his earliest muses .