The author has attempted to give a brief description of the numerous species of worms parasitic in man and the commoner domestic animals (dog, cat, pig, cattle, sheep, goat, camel, horse and relatives, fowl, turkey, guinea-fowl, duck, goose and pigeon). These descriptions are models of conciseness and it is difficult to see how the author could have condensed more information within such limited space. Even such an important parasite as Necator americanus receives less than a page. As a result of this deliberate condensation the descriptions are limited to such rigorously zoological subjects as occurrence, morphology and outlines of life histories. The descriptions are arranged according to zoological classification, with introductory accounts of the larger divisions, such as classes, families, orders and genera. The common synonyms of the more important species are listed, but the author does not discuss the seemingly interminable questions of nomenclature—an omission for which most workers