A Complete Guide to Heraldry by Arthur Charles Fox-Davies

9. Sir Humphrey Stafford, Earl of Stafford, 1429-1460. Arms: or, a chevron

gules. Crest: out of a coronet gules, a swan's head and neck proper, beaked gules, between two wings also proper. Mantling: the dexter side, sable; the sinister side, gules; both lined ermine. Black and gules, it may be noted, were the livery colours of Buckingham, an earldom which had devolved upon the Earls of Stafford.