This is not one of the Grimm tales ordinarily illustrated--or read to younger children--for good reasons. ""Once upon a time,"" as it's phrased here, ""a boy with a caul was born to a poor couple."" We hear, of course, that the caul is a good-luck sign; but what it is, or why it's supposed to bring luck, we're never told. The story has two distinct parts. To thwart the boy's predicted marriage to his daughter, the king tries to drown him in infancy; later he tries to arrange, through a sealed message, that the boy be slain. But sympathetic robbers substitute a message calling instead for the boy to be married to the king's daughter--so the prophecy comes true, after all. That's the first half of the tale, which turns on words (the prophecy, the switched messages) and has almost no visual values. In the second half, the vindictive king orders the young bridegroom to fetch three golden hairs from the head of the devil. And with the aid of the devil's grandmother (the one strong-flavored character), he gets not only the three hairs but the answers to three conundrums posed en route. . . one of which also enables him to dispose of the king forever. The eventful journey is represented by a single calm, motionless picture; the figures (as throughout) are limp; even the marvelous image of the grandmother plucking hairs from the devil has little wiliness or zest. It's a story, all told, that's more verbal than pictorial--and one that, if it's to be illustrated at all, needs sharper, tauter handling.