In the "Sierra Club Wildlife Library," a book with elegant full-color photos but a text that is merely adequate, Sattler's excellent The Book of Eagles (1989), a book of similar difficulty and length, has set a standard difficult to match. For example, Lang states only that the "Eagle eggs are about the size of chickens' eggs," while Sattler devoted a whole page to describing eagles' eggs, noting variations in color, texture, and size (the smallest like chickens' eggs, but the largest as big as the plastic eggs used to package panty hose). In describing Africa's vulturine eagle, Lang says, "It is the only eagle. . .that is a vegetarian." Sattler disputes the vegetarian claim: ". . .[it] also eats small fish, crabs, and frogs." Lang also doesn't provide scientific names; if an additional source is warranted, however, Lang should be considered, primarily for its excellent photos. Index.