ATTACK OF THE DERANGED MUTANT KILLER MONSTER SNOW GOONS <i> by Bill Watterson (Andrews & McMeel: $8.95).</i>

The latest anthology of “Calvin and Hobbes” demonstrates how a comic strip evolves. Since Watterson began drawing the strip in 1987, the rambunctious Calvin and his intrepid tiger-companion Hobbes have grown less angular and more appealingly rounded. The changes in their appearance are due in part to the process psychologists call shaping: When an artist continually redraws a figure, his wrist tends to move in a circular pattern. As Watterson has polished the graphic appearance of his characters, he’s also deepened his explorations of their psychology. The hilarious runaway sequences in which Calvin imagines that he’s cloned his good side to go to school for him, or that his hideous snowman has replicated itself into a army of “grotesque, evil, demented monsters,” reflects the artist’s unmatched grasp of the uninhibited world of a child’s imagination.