 The second and third orders used partly Patrick's mass and partly one of British origin, and in the case of the third order Roman modifications were also introduced.The working of the "Catalogus" seems to imply that the first and second orders were Quartodecimans, but this is clearly not the meaning, or on the same argument the third order must have been partly Sextodecimans — if there were such things — and moreover we have the already mentioned statement of St. Wilfrid, the opponent of the Celtic Easter, at the Synod of Whitby, that such was not the case.Tirechan can only mean what we know from other sources