MacMaurice

The MacMaurice sept of the Clan Buchanan

Morrice, Morris, McMaurice, Morrison (of Perthshire only)

According to Buchanan of Auchmar, these names are derived from an illegitimate son of Maurice, Laird of Buchanan, during the reign of Robert I.  They may also have originated with Maurice, who was the illegitimate son of Walter Laird of Buchanan, during the reign of James III. 

Descendants of the latter are found in the area between Stirling and Culross.