The first all-photographic field guide. Each of the 474 identification pictures is a full-color photograph of a fossil. Sponges, corals, trilobites, shells, teeth, bones, and many other types are represented. Also included are 33 color photographs of fossil-bearing rocks and outcrop formations, plus 15 maps. The first guide to be organized visually with a key. Arrangement by shape and color makes identification quick and easy. More than 700 fossils are covered, 420 of them in full detail. From the National Audubon Society.