Sentence:  Prior to the passing of the ordinance of the Scottish University Commissioners, the <WSD>Regius professors</WSD> then in office had their share of the graduation fees as well as the parliamentary salary, and the Commissioners reserved to the then holders of those Regius Chairs the privilege of still taking their share of the graduation fees so long as they lived; 
Meaning of the word marked with <WSD> tags:  (rare) (regius professor)