A REVIEW OF THE FLOUNDERS BELONGING TO THE GENUS PLEURONICHTHYS. By Edwin Chapin Starks and William Francis Thompson, Of Stanford University, < 'alifornia. In the following paper six American species, and one Asiatic species, of the genus Pleuronichthys are described, including two new-ones. Types and cotypes of the new species are deposited in the U. S. National Museum. The distribution of each species is known only so far as specimens at hand indicate, for former records show Pleuronichthys ccenosus (representing four species) to occur along (he entire wesl coast of the United States. The species of the ccenosus group are very well separated geo-graphically, though toward the limits of the area inhabited by each species there is more or less overlapping with areas of neighboring species. Specimens are in the National Museum or in the Stanford University collections, showing the following distribution: Pleuronichthys nephelus, new species, is known only from Puget Sound. Pleuronichthys ccenosus is found from San Francisco to San Pedro, California. Along the great length of coast between San Francisco and Puget Sound a species of this group occurs, but no records indi-cate whether it is Pleuronichthys ccenosus-or Pleuronichthys nephelus, or whether, as is probable, both are found at some point. Pleuronichthys ritteri is known from San Pedro southward along nearly the entire west coast of Lower California, or south to latitude 24°. (Albatross station 3042.) I'll iiron'icltlhijs oci llatus, new species, is known from rather deep water only from near the northern end of the Gulf of California. Pleuronichthys <l<cnrr< ns is known from San Francisco southward to the Santa Barbara Islands. Pleuronichthys verticalis is known from San Francisco to the (lull' of California, or along the entire known range of three of the species that have been confused with Pleuronichthys ccenosus. Pleura r i ir/it/njs eornutus is known along the coast of Japan north to Hakodate. The drawings of the new species accompanying this paper are the work of Mr. W. S. Atkinson. Proceedings U. S. National Museum, Vol. 38— No. 1744. 277