The first all-photographic field guide, now revised with new photography and text. Descriptions of 390 species have been brought up to date with the most current, widely accepted checklist of North American mammals. The descriptions are keyed to 374 full-color photographs of the animals as they appear in their native habitats, often displaying characteristic behavior. The National Audubon Society Field Guides are the first to be organized with a visual key. Species are grouped according to type, shape, and size, and keyed with helpful thumb-tab silhouettes to make identification quick and easy. A second key permits the reader to identify animals by their tracks. The descriptive text covers the 11 orders of land mammals present in North America north of Mexico, and includes range maps, black-and-white illustrations, and track drawings. A state-by-state range guide enables the user to make quick identification of small mammals by geographic location.