A CHICK HATCHES

At the very beginning children may have difficulty making out the shadowy form of the chick's embryo and identifying the ""dark spots"" which will develop into its heart and eye, but as the chick grows so does the fascination of Wexler's color and black-and-white close-ups--of the seven-day fetus floating under a balloon-like yolk, the eleven-day fetus with its enormous eyes and ""goose bumps"" forming on its skin, and the downy, fully-formed eighteen-day fetus still attached to a yolk sac that's gradually being ""drawn into"" its body. Cole's spare text introduces a few terms, such as allantois and amniotic sac, but it's no more difficult than the accompaniments to Wexler's more conventional views of puppy and calf births. And the final portrait of a self-satisfied two-day-old chick puts the whole process in perspective.