Among the most considerable of M. Bédier's achievements in his study of the Tristan legend was his demonstration by means of proper names that the tradition, in some form or other, must have passed from Pictland through Wales and Brittany into France and England. Although the researches of Miss Schoepperle have shown the influence of Irish aitheda, although the work of M. Loth has made it impossible to ignore the share of Cornwall, and Dr. Brugger's studies of the man Bleheris and of the name Loonois add to our knowledge of the origin and transmission of the story, yet M. Bédier's scheme still stands out as the first reasonably full and acceptable account of the derivation of any Arthurian romance. Now it is noteworthy that so important a result rested in large measure on the origin of the names inbedded in the tradition. Had the onomastic studies of Rhys, Miss Paton, Bruce, and Dr. Brugger been as generally convincing as those of M. Bédier, scholars would not still be so far apart in their interpretation of the development of the Round Table cycle. Thus far the only body of facts, apart from the Tristan branch, to which all parties subscribe is that the personal names Arthur, Kay, Bedivere, Modred, Guinevere, Merlin, Maheloas, Caradoc Briebras, Ider the son of Nu, Ivain son of Urien, Uther, and other proper names such as Escalibour, Pridwen, and Tortain, are derived from the Welsh. But the materials for further study are, as the Index to Sommer's seven volumes of French romance and Miss Blount's unpublished onomasticon show, very rich, and nothing seems to stand in the way of real advance in this field of research if only we can formulate and apply certain criteria which will at the same time fit the somewhat lax conditions of name-development and also be sufficiently rigorous to give assured results.