"I am Amos Silkworth's great grandson. I have quite a number of his photographs, and remember his studio logo from my childhood. Amos Jr. married Mary Biffar in 1985. Mary's father Henry Biffar originated the photography studio, so we can assume that the Silkworth name did not appear independently until after that date. By the turn of the century it seems that Amos had earned his fortune in the photography business and retired to Mattituck, N.Y."
So it looks like we can date the photograph of the man to between 1885 and around 1900, so he is clearly of the same generation as the woman, and as Julia and Patrick, though I'd be against assuming that the man and the woman are husband and wife - wouldn't it be reasonable to think that a couple having their pictures taken would go to the same photographer? I wouldn't say they can't be man and wife, just that I don't think it's safe to assume they are until we've identified them.