Monroe has a wild imagination. No one can see it but him. He usually keeps it on a leash,"" but one day, while Monroe is taking a bath, his imagination runs away with him. . . all the way to a desert island where chocolate chip cookies grow on trees. Readers can see from the start that Monroe's imagination is a tusked, blue, benign-looking, snaggle-toothed beast; and even if they don't catch all the word play they'll enjoy the neat, very simple joke. Brooks, an art student and recent high school graduate, has hitched up his own imagination and pulled out a few lengths ahead of all those tame, too-literal representations of kids' imaginary companions.