A NEW GENUS AND TWO NEW SPECIES OF CRUSTA-CEANS OF THE FAMILY ALBUNEID^E FROM THE PA-CIFIC OCEAN; WITH REMARKS ON THE PROBABLE USE OF THE ANTENNUL.E IN ALBUNEA AND LEPIDOPA. By James Vj. Benedict, Assistant Curator of Marine Invertebrates. During-1889 the U. S. Fish Commission steamer AJhatross, engaged in explorations off the coast of California and Lower California, in the course of which a considerable amount of zoological material was obtained. Among-the inv-ertebrates transmitted to the U, S. National Museum were three specimens of an anomuran crustacean, of an undescribed genus and species, which are characterized below. I take this opportunity to describe also a new species of Alhunea., based on a single specimen obtained by Mr. C. N. E. Eliot at Samoa. It gives me great pleasure to associate with this species the name of the collec-tor, a well-known officer of the British diplomatic service, and an ardent student of zoology. LOPHOMASTIX, new genus. Eye peduncle very slender, not articulated in the middle. Antenna? without accessory joint. Flagellum of antenna? rather long, with nine joints, each about two and one-half times as long as broad; joints setose. Antennula? much shorter than antenna?, sparsely setose, mul-tiarticulate. The exopod of the outer maxillipeds has a slender ril)-bon-like second article, the distal end of which bears a long-dense tuft of hair. The carpal and propodal joints of the maxillipeds are broad, the distal article is yqvj much narrower and presents an elongated oval surface. The distal inner margin of the merus is armed with two spines. Type. — L. diomedese. LOPHOMASTIX DIOMEDEi^, new species. The eyestalks are slender, slightl}'. swollen at the cornea. The basal article of the antenna is l)road and pectinate; the following joint is about as broad as long, Avhile the third is very short and seems to be nearly conate with the penultimate, which is long and cylindrical; the Proceedings U. S. National Museum, Vol. XXVII— No. 1367.