A book about dinosaurs, from a science writer (Batman, 1991 etc.) with a strong track record, who here may have misjudged his audience. The picture book format will turn away grade-schoolers old enough to grasp such complicated concepts as fossils, which are introduced but not fully explained. The writing is skillfully on target, if a bit formal, for younger dinophiles. They will find the full-color, detailed illustrations convincingly scaly and realistically ugly; especially good is Heyer's pachyrhinosaurus with its swirling multihued skin. It illustrates Pringle's comment that fossils teach nothing about the colors of dinosaurs, nor about the sounds they made. (Nonfiction. 4+)