The designation of Giants’ players as “World’s Champions” dates this issue to 1906. The 3-1/2" x 5-1/2" cards have a black-and-white photo surrounded by a greenish or reddish-brown tone wooden-look frame with a plaque printed in the bottom border. Backs are printed in brown with typical postcard markings and include mention of “Ullman’s ’Art Frame’ Series.” This checklist is likely not complete. The card of “Harry” (name actually Henry) Mathewson is the only known baseball card appearance of Christy’s kid brother.