The final decision to which Dr Skene comes in his great work is that the clans, properly so called, were of native origin, and that the surnames adopted by them were partly of native and partly of foreign descent. Among these native Highland clans he unhesitatingly classes the Mackenzies, the clan Gillie-Andres or Rosses, and the Mathesons, all of whom belong, he says, to the tribe of Ross. In his first work on the Highlands and Highland Clans he draws the general deduction, based on all our existing MS. genealogies, that the clans were divided into several great tribes, descended from a common ancestor, but he at the same time makes a marked distinction between the different tribes which, by indications traceable in each, can be identified with the earldoms or maormorships into which the North of Scotland was originally divided. By the aid of the old genealogies he divides the clans into five different tribes in the following order:- (1) The descendants of Conn of the Hundred Battles; (2) of Ferchar Fata Mac Feradaig; (3) of Cormaig Mac Obertaig; (4) of Fergus Leith Dearg; and (5) of Krycul. In the third of these divisions he includes the old Earls of Ross, the Mackenzies, the Mathesons, and several other clans, and to this classification he adheres, after the most mature consideration, in his later and greater work, the 'History of Celtic Scotland.' THE REAL CELTIC ORIGIN. It is now most interesting to know who the ancient Earls of Ross, from whom the Mackenzies are really descended, were. The first of these earls of whom we have any record is Malcolm Mac Heth to whom Malcolm IV. gave Ross in 1157, with the title of Earl of Ross, but the inhabitants rose against him and drove him out of the district. Wyntoun mentions an Earl "Gillandrys," a name which we believe is derived from the common ancestor of the Mackenzies and Rosses, "Gilleoin-Ard-Rois," as one of the six Celtic earls who besieged King Malcolm at Perth in 1160. Skene is also of opinion that this Gillandres represented the old Celtic earls of Ross, as the clan bearing the name of Ross are called in Gaelic Clann Ghilleanrias, or descendants of Gillandres, and may, he thinks, have led the revolt which drove Malcolm Mac Heth out of the earldom. The same King, two years after the incident at Perth, gave the earldom of Ross to Florence, Count of Holland, on that nobleman's marriage with His Majesty's sister Ada, in 1162, but the new earl never secured practical possession ['Celtic Scotland,' Vol. III., pp. 66-67.] He is, however, found claiming it as late as 1179, in the reign of William the Lion.