John William Staley
(probably)

This photo not labeled except for a photographer's name and location of photo: R.H. Mann, Viriginia. Ill. Also on front are the words "The Plaque" and "Patented Oct. 10th and Dec. 5, 1882." The photo has a raised circle around the portrait, indicating it was probably intended for a circular frame, perhaps a bubble glass.
This picture is probably John William Staley taken at around age 30. The resemblance to Edward Winthrop Staley suggests that it is difficult to be certain which family member is pictured. The Virginia, Illinois location with a patent date of 1882 gives useful clues. Virginia, Illinois is where John William Staley married Emma Dickinson in 1879. He could easily have returned within a few years and had this portrait taken. In 1882 John William would have been 28. It seems highly unlikely that the patent date of 1882 would still be used on a picture after 1900 when Edward Winthrop would have been about the age of the person in the photo.
Other possibilities include John William's siblings and since we have no photos of these men to compare, they cannot be ruled out: Samuel Bruce, Thomas F., and Abraham L..