I am a descendant of James Stewart, fourth son of Alexander Stewart, known as the "Wolf of Badenoch." In The heraldry of the Stewarts, with Notes on All the Males of the Family, Descriptions of the Arms, Plates and Pedigrees, by George Harvey Johnston, James' arms are described as "recorded by Grant of Rothiemurchus in 1755 as Gold, a fess chequy blue and silver, between three black wolves heads couped, (Lyon Register. Plate III., Fig. 39."

I do not have access to the original of Johnston's book, nor an original of the Lyon Register. Can anyone help me determine what these arms would look like?