O’Hart

In John O’Hart’s Irish Pedigrees or the Origin and Stem of the Irish Nation (5), he shows Carton and Cartan as modernisations of MacCartan.

MacCARTAN chiefs of Kinelarty , Co Down. Fergan, a brother of Connall, who is 92 on the “Guiness” pedigree, as the ancestor of MacCartain; modernised Cartan, Carton, MacCartan, and Maccartan.

O'Hart then confuses Cartin and Carleton, but recognized the connection with the Clan Diarmiada who are elsewhere described as chiefs of the Ui Mhic Carthainn.

The O'Cearbhallins (O'Carolans, or Kerlins), a name sometimes anglicised "Carleton," were chiefs of clan Diarmaida, now the parish of Clandermod or Glendermod, in Derry.

A fuller extract follows:

"On page 320 MacCARTAN chiefs of Kinelarty , Co Down. Fergan, a brother of Connall, who is 92 on the “Guiness” pedigree, as the ancestor of MacCartain; modernized Cartan, Carton, MacCartan, and Maccartan.

THE IRISH CHIEFS AND CLANS The following chiefs and clans, not given by O'Dugan, are collected in Connellan's Four Masters, from various other sources: 1. O'Criochain or O'Crehan (mentioned in the Annals of the Four Masters, under A.D. 1200), chief of Hy-Fiachra, a territory which comprised the parish of Ardstraw, and some adjoining districts in Tyrone. 2. O'Quinn, chief of Moy Lugad and of Siol Cathusaigh (a quo Casey), as given by the Four Masters, under A.D. 1218. Moy Lugad, according to the Books of Lecan and Ballymote, lay in Keenaght of Glengiven, county Derry. 3. The O'Cearbhallins (O'Carolans, or Kerlins), a name sometimes anglicised "Carleton," were chiefs of clan Diarmaida, now the parish of Clandermod or Glendermod, in Derry. "

Reference

5 John O’Hart. "Irish Pedigrees; or, the Origin and Stem of the Irish Nation" by John O'Hart, Fifth Edition, 1892