The Appleton Collection includes more than 2,000 glass photographic negatives, taken in Media, Pennsylvania and vicinity from 1888 to 1909. Media Historic Archives received the collection in 1988, but until 2018 most of these pictures had never been seen by the public.
This may be "Timmie," the pet money of Dr. and Mrs. Morton P. Dickeson, as described in the animal's obituary in the Chester Times, March 29, 1919. The monkey was 13 years old. However, Timmie figured in a lawsuit that was covered by the Philadelphia Inquirer on January 3, 1912, page 2, and the photographs of Timmie accompanying this article do not look like the monkey in Appleton's photograph. So the verdict is that this monkey remains anonymous.