A Field Guide to the Birds. Large Format Edition. The Birder's Bible for more than sixty years, now in large, easy-to-read format. Roger Tory Peterson's classic art is enlarged to new proportions, making bird identification easier than ever. 390 newly updated range maps are located next to the descriptions, opposite the illustrations. Features the unique Peterson Identification System, which has never been surpassed as a tool for field identification and is available only in Peterson Field Guides.