After a few introductory pages on the structure of the egg, the development of the chick embryo, the early cell division of a sea urchin egg, and some general differences in egg production in different classes of animals, McClung surveys egg laying, hatching, care, and so on among the whole line of animals from jellyfish, worms, and other lower animals to placental mammals including humans. He notes peculiarities among different animals within each class--catfish fathers, for example, carry the females' eggs in their mouths for as long as a month; and the male midwife toad carries his mate's eggs on his back--and he touches as well on the nests of different birds, child care or its absence among different reptiles, and other matters related to egg processes. The result is a clear, straightforward, suitably-illustrated compendium of information, although without the detail or thought-provoking interest of Dorothy Patent's books on the different animal groups "". . . and How They Reproduce.