Historical.—Our knowledge of the cestode parasites of marine fishes is due almost entirely to the work of Linton in North America, Shipley, Herdman and Hornell in Indian waters, Zschokke and Beauchamp in Europe. We know nothing regarding the tapeworms found in fishes in South America, round the coast of Africa, or in the Arctic; and our knowledge of those found in the Far East is limited to descriptions of about ten species by Yoshida. It will, therefore, be apparent that there still remain large areas to be investigated.