More on Cain-coloured Beard from Infoplease:

• Cain-coloured Beard - Cain-coloured Beard Yellow, symbolic of treason. In the ancient tapestries Cain and Judas are ...
• William Shakespeare: Merry Wives of Windsor, Act I, Scene IV - What, John Rugby! I pray thee, go to the casement, and see if you can see my master, Master Doctor Caius, coming. If he do, i' faith, and find any bod
• Dictionary of Phrase and Fable: C - Definitions, origins, and illustrative excerpts for words, phases, and literary allusions starting with "C"