Just about everyone is familiar with the awe-inspiring dinosaurs of long ago: Tyrannosaurus rex, brontosaurus, pterodactyl. But they weren't the only tough guys in town. In fact, before, during, and after the Age of Dinosaurs (also called the Mesozoic era), creatures beyond our wildest dreams roamed the earth, paddled the seas, and flew through the sky. Howard Zimmerman, author of Dinosaurs! The Biggest Baddest Strangest Fastest, shares some incredible facts about these bizarre reptiles and mammals. Take, for example (before it takes you!), the Diatryma, a giant flightless bird (up to 9 feet tall) with thickly muscled legs, three large clawed toes on each foot, and a huge, powerful, hooked beak. Or the monstrous, sea-dwelling Kronosaurus, over 45 feet long, its 10-foot-long skull filled with needle-sharp teeth. Then there was the ferocious Hyaenodont, a mammal that, like modern hyenas, fed on the bodies of dead animals, as well as hunting and killing its own prey. Zimmerman divides this oversize volume, lavishly drawn by the world's top illustrators of prehistoric animals, into three main sections: Pterosaurs: The Sky Dragons; Marine Reptiles; and Mega-Mammals and Other Prehistoric Beasts. Each description is fairly succinct, easy to follow, and packed with facts and details about the animals' size, eating habits, looks, and when and where it lived. Zimmerman also includes a listing of Web sites for additional information. Utterly fascinati