But though British crests are presumed to be subject to the recognised marks of cadency, as a matter of fact it is very seldom indeed that they are ever so marked, with the exception that the mark used (usually a cross crosslet) to signify the lack of blood relationship when arms are assumed under a Royal License, is compulsory. Marks of distinction added to signify illegitimacy are also compulsory and perpetual. What these marks are will be dealt with in a subsequent chapter upon the subject. How very seldom a mark of difference is added to a crest may be gathered from the fact that with the exception of labels, chiefly upon the Royal crest, one crest only amongst the Plantagenet Garter plates is differenced, that one being the crest of John Neville, Lord Montague. Several crests, however, which are not Royal, are differenced by similar labels to those which appear upon the shields; but when we find that the difference marks have very much of a permissive character, even upon the shield, it is not likely that they are perpetuated upon the crest, where they are even less desirable. The arms of Cokayne, as given in the funeral certificate of Sir William Cokayne, Lord Mayor of London, show upon the shield three crescents, sable, or, and gules, charged one upon the other, the Lord Mayor being the second son of a second son of Cokayne of Sturston, descending from William, second son of Sir John Cokayne of Ashborne. But, in spite of the fact that three difference marks are charged upon the shield (one of the quarterings of which, by the way, {345} has an additional mark), the crest itself is only differenced by one crescent. These difference marks, as applied to arms, are in England (the rules in Scotland are utterly distinct) practically permissive, and are never enforced against the wish of the bearer except in one circumstance. If, owing to the grant of a crest or supporters, or a Royal License, or any similar opportunity, a formal exemplification of the arms is entered on the books of the College of Arms, the opportunity is generally taken to add such mark of cadency as may be necessary; and no certificate would be officially issued to any one claiming arms through that exemplification except subject to the mark of cadency therein depicted. In such cases as these the crest is usually differenced, because the necessity for an exemplification does not often occur, except owing to the establishment of an important branch of the family, which is likely to continue as a separate house in the future, and possibly to rival the importance of the chief of the name. Two examples will show my meaning. The crest of the Duke of Bedford is a goat statant argent, armed or. When Earl Russell, the third son of the sixth Duke of Bedford, was so created, the arms, crest, and supporters were charged with a mullet argent. When the first Lord Ampthill, who was the third son of the father of the ninth Duke