Clessammor, son of Thaddu and brother of Morna (Fingal's mother), married Moina, daughter of Reuthamir (the principal man of Balclutha, on the Clyde).  It so happened that Moina was beloved by a Briton named Reuda, who came with an army to carry her off.  Reuda was slain by Clessammor; but Clessammor, being closely pressed by the Britons, fled, and never again saw his bride.  In due time a son was born, called Carthon; but the mother died.  While Carthon was still an infant, Final's father attacked Balclutha, and slew Reuthama (Carthon's grandfather).  When the boy grew to manhood, he determined on vengeance; accordingly he invaded Morven, the kingdom of Fingal, where Clessammor, not knowing who he was, engaged him in single combat, and slew him.  When he discovered that it was his son, three days he mourned for him, and on the fourth he died.—Ossian: Carthon. (The Reader's Handbook of Famous Names in Fiction, &c., Brewer, 1899)