The primary purpose of this compilation is to facilitate for pertinent literature in the searches involving digenetic trematodes from fines. The index may be used by the investigator to determine what, Af any, 14torature has appeared concerning the animal or group of animals with which he is working; and the literature is cross-indexed in such a way that it may be approached from the various angles commonly used in trematodes investigations. There are included, for example, an index to hosts, an index to larval stages of development and a partial geographic index to adult trematodes of fishes.