_Tree frogs._--Tree frogs enclosed in a room overnight were said to effectively clear it of cockroaches (Marlatt, 1915); on sugar plantations in Australia, these amphibians were encouraged in houses and kept as pets because they hunted and devoured large brown cockroaches (Froggatt, 1906). _Birds._--In Guadeloupe, Dutertre (1654) claimed that all the fowls of the country were fond of small cockroaches and lived on practically nothing else. In Hawaii (Zimmerman, 1948) and in the Lesser Antilles (Ballou, 1912) cockroaches are eaten by poultry whenever the birds can find them. In Puerto Rico, Wetmore (1916) stated that owls kept in houses feed extensively on cockroaches; the stomach of one owl which had been kept in a native house was filled entirely with cockroaches. In British Guiana, Beebe (1925) found that cockroaches were eaten by 27 species of birds. _Reptiles._--H. (1800) claimed that two lizards cleared his house of the "true brown cockroach" and suggested that lizards be used for cockroach control because the reptiles are docile and harmless. On Arno Atoll geckos and night-feeding skinks eat large numbers of cockroaches (Usinger and La Rivers, 1953). According to Wolcott (1924) the number of cockroaches eaten by lizards is surprisingly large considering the nocturnal habits of these insects. Beebe (1925a) kept geckos in a bungalow to help control _Periplaneta_ and _Pycnoscelus_. _Mammalia._--Cowan (1865) stated that in England hedgehogs were often kept domesticated in kitchens to destroy cockroaches. This writer also stated that a lemur was kept on board ship to destroy cockroaches. Large numbers of the American and Australian cockroaches were eaten by the mongoose in Hawaii (Perkins, 1913). ACKNOWLEDGMENTS We would have been unable to complete this review without the help of many people who have generously given us their time and the benefit of their special experience. We are exceedingly grateful to these individuals for they have contributed much to whatever merit this work possesses; we alone are responsible for the deficiencies and inaccuracies that remain in the text. Dr. A. B. Gurney, Entomology Research Division, U. S. Department of Agriculture, and J. A. G. Rehn, Academy of Natural Sciences of Philadelphia, have given us much help and advice throughout the preparation of this monograph. Both have patiently answered our many queries, and Mr. Rehn allowed us free access to his large collection of cockroach literature. We are especially pleased to thank them for their many favors. Many persons have determined at our request the identity of specific organisms. These individuals are cited in the text and to them we extend our thanks. We thank our colleagues, cited in the text, who have made their unpublished observations available to us. We also thank the individuals and organizations for the use of photographs and/or drawings for which they are credited in the accompanying legends.