I have a family tree of Clan Donald that is hand written and appears to be quite old. I received it from my father who received it from my great uncle, Monsignor Ranald MacDonald. I originally thought he had written it, but it was stored in a tube that had a mailing address TO Msgr Ranald MacDonald. There is no authors name on the document (24" X 35"). There are a few dates with the names and an occasional comment or title. There are only a few females listed. It actually has the line extending back MANY generations prior to Somerled and even has the line extending back to Conn, Ard Righ. It does name Ian Ruadh and under the name (Clan Ian Ruadh of Knoydart). The line from Somerled to Martin is as listed: Somerled,Reginald, Donald, Alastair Mor, Hector Ard, Hector Og, Charles, Ewen, Angus Buidhe, Niel, Ian Ruadh, Roderick, Dugall, John, Angus, Ian (John), Donald, Martin, Ewen, Ronald (Archbishop of Pictou). I believe there are some errors in the line and there certainly many siblings omitted.
I have just made some photographic archival pictures of this document. The original is getting framed and returned to my mother. I will write again to discuss my own personal line in Clan Donald.
Hope this will add to the discussion.