Gilmore,
The Reverend Frederick Lewis Weis did not attempt medieval genealogy. He was strictly interested and published in the American Colonial period. I have had a chance to dig through many of the reference works in my personal library on this.
To add to the above on George Robertson
b: Perthshire, Scotland 1662. St Andrews, Scotland M.A. 1683. Ordained London, England 20 Dec 1691. m. 1698 Mary Worsham. Record of a son James b., 1708.

Francis Fontaine b.1697, son of James Fontaine; K.B. for VA 30 Dec 1720; settled Manakintown, King William Parish (Powhatan), VA 1720-1721. Settled Saint Margaret's Parish (Caroline) VA 1721-1722; settled Saint Peters Parish (New Kent) VA 1722. Settled Yorkhampton Parish (York) VA 1722-1749; Professor of Oriental Languages, William & Mary College 1729. d. Yorkhampton Parish, 1749.

The Blue Book of Genealogical and Hereditary Socities is rather fat, for there are many. I belong to several, and one of them inspired me to return to my kilted (Scot) heritage. Ihave only joined a few groups, as I really need to feel as if I can contribute to the group before I take the time to do all that genealogical research and documentation.
Slainte