Gone are the days of Holly riding a baby bronto in Land of the Lost and Raquel Welch fending off stop-motion dinosaurs in One Million Years B.C. Whether we're at the movies or in a museum, we want the straight, scientific scoop on dinos--especially if "we" happen to be kids. Enter the Ultimate Dinosaur Book, a fully illustrated field guide to the Mesozoic. Working with the Natural History Museum in London, publisher Dorling Kindersley has assembled hundreds of color photos, diagrams, and drawings, while enlisting the expert assistance of author David Lambert (winner of both the New York Academy of Sciences Award and the Children's Book Council Award). Beginning with straightforward sections on evolution and dino behavior and physiology (any self-respecting kid should be able to tell a "bird-hipped" dinosaur from a "lizard-hipped" one), the book launches into impressive, illustrated profiles of more than 50 different dinosaurs. From the Theropods to the Marginocephalians, each specimen gets a two-page spread (or more, for the big-name beasties). The profiles will likely teach you a thing or two you didn't know (eight hearts in the Barosaurus?), and a few you did (Stegosauruses regulate heat with their plates, of course), but the book's neatest feature may be its "A to Z of Dinosaurs" in the back: the comprehensive list includes every currently known dinosaur genera, with a pronunciation guide and short description. With Lambert's precise but friendly text and DK's legendarily clean, evocative graphics, the Ultimate Dinosaur Book is as close as you'll get to a walking tour of the Mesozoic. (And, hey, somebody tell Holly: that was a baby Apatosaurus she was riding.) --Paul Hughes