A chance delight! I discovered this while opening up an antique gold gessoed frame in order to reuse it, and here was this, used as backing paper for a photo, sandwiched between a few other layers. Surely a product of toning, perhaps it once backed a pair of paper cutout animals, which left their silhouettes behind. Looks like a cat and horse to me, though perhaps a dog and an especially graceful cow! Whatever the case, the happiest of accidents--subtle like a watercolor, and quite elegant and poetic feeling. And I've had this terrific old green painted frame sitting around in wait of just the right thing, which I think this is. 

Framed: 8 1/4" x 6 1/4".  Paper: 6 5/8" x 4 5/8". I've photographed in and out of the frame. There's an old crease to the card (light weight card rather than paper) running vertically between the animals--I don't think detracting, just of a piece with it.