Reports on the dredging operations off the west coast of Central America to the Galapagos, to the west coast of Mexico, and in the Gulf of California, in charge of Alexander Agassiz, carried on by the U.S. Fish Commission steamer “Albatross,” during 1891, Lieut.–Commander Z.L. Tanner, U.S.N., commanding. VI. Preliminary descriptions of new species of Crustacea.