The photo is 6" x 7.5", on a card 6.5" x 8.5". The front of the card is stamped "Vaupel", and "989 Third Ave, N. Y.". The back of the card is a large engraving, "H.M. Vaupel. | Artist and Photographer | 989-3rd Avenue | New York | S.E. cor. of 59th St. | The instantaneous process used exclusively."
Herman M. Vaupel was at that address from 1884-1899 (at least), while living at 1087 Second Ave. Listed as only an artist, at the same addresses, in 1882.
The subject of the photo is possibly Arthur Vaupel (b. 1883), the son of the photographer, which would date this to around 1888.