This is my favorite trade card I've found, c. 1890 or so I believe, and a pretty rare one--the only other copy I can find of it out there is held int he Cornell University Library Rare and Manuscript Collection. What a face, and what a watermelon, and how much fun I think it would have been to visit Parker & Wood's Agricultural Warehouse and Seed Store (with celebrated ice tools!) in Boston, located just a few steps from historic Faneuil Hall.
5 1/8" x 3 1/16". Good condition, with a little writing in pencil on front and back, which appears to read Parker and Wood on front and perhaps a note about location on the back.