Extract from the "Historical & Critical Remarks on Prynne's History" commonly called Ragman Roll p 23.
Dominus Nicolaus de Rutherford is the ancestor of the Rutherfords of that Ilk who came to be designed Domine ejusdem in King Robert II's time. They were a family of reputation and held the most part of their estate of the Earls of Douglas. The family split betwixt an heir-male and heirs of line, in King James IV's reign. Rutherford of Edgerston was the heir-male, and now represents the principal original family, and the Earl of Traquair is the heir of the line, who carries the arms of Rutherford in his achievement.