James’ descendants are often called the MacHamish line.
The term MacHamish was an indication of which Gunn family line was meant for legal and other reasons; there were many Gunns with the same name in the highlands of Scotland so the need to clarify which Gunns were under discussion was obviously of real importance. Mark Rugg Gunn says ‘William son of James, succeeded his father and was known as Uilleam mac Sheumais; he was the first MacHamish’. Another version of William’s name is ‘Uilleam - Mac-Sheaumais - Mhic-Chruner’ ; ‘William son of James, grandson of the Coroner’. Note the lack of any mention of Chief of the ‘Clan’ Gunn and, in fact, any mention of the surname Gunn in William’s names.
If the MacHamish line had been Chiefs of the Clan Gunn as Gunn myth would have it, then as Chief of the Clan Gunn is how the individuals would have been known in legal and other documents as Chief of a Clan was far more important than being ‘named’ after the basically anonymous James. In other words, there is no reason for the term MacHamish to exist if the line had been Chief of the ‘Clan’ Gunn, as Chief of the ‘Clan’ Gunn would have made the term MacHamish irrelevant.
The use of MacHamish in Gunn history again shows that the Gunns did not have Clan Chiefs.
 I have seen a document written on Lord Strathnaver’s behalf dated 23 September 1738 which is part of the Sutherland Estate papers held by the National Library of Scotland. The document twice uses the word Mckeamuish, and once Mckaimish, when referring to this Gunn MacHamish line - and it has no mention of a ‘Clan’ Gunn Chief in the document. MacHamish is an anglicisation of these 1738 Mckeamuish / Mckaimish spellings.
 To rely on place to identify a Gunn family line (such as Gunn of Wick) is inadequate as many Gunns could live in one named area – the clear identification is by family line such as MacHamish..
 Page 166 MRG
 Page 179, James Browne, A History of the Highlands and of Highland Clans, A Fullarton and Co, Volume 1, published 1840.