I have also found this on Google, links the family of George Washington Goss to Henry Plantagenet (Henry III, King of England 1216-1272). Not too sure about that bit, but it does have a date of birth for James Clark Goss of 01 Feb 1851, which is the same date (but different year)as the gravestone for him in Texas.
http://familytreemaker.genealogy.com/users/g/i/l/Nicolette-K...