This is Portrait of Mademoiselle Marie Fantin-Latour (1859) by Henri Fantin-Latour (French, 1836-1904). According to the tumblr site where I found it,
This portrait of the artist’s sister was rejected by the Salon of 1859 perhaps because of its austere, understated composition. French academic painting still favoured grand narrative themes painted in sharp detail. Fantin-Latour’s treatment of light in terms of tone rather than color recalls the work of both Degas and Whistler, both friends of the artist.
Fantin-Latour was celebrated for his flower paintings, and had a glorious rose named after him. Here it is. Time I got one for my own garden, methinks.