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Show 118 MR. F. E. BEDDARD ON ISOPODA COLLECTED [Feb. 2, claw ; in the posterior appendages this terminal joint is furnished at its distal extremity with a circlet of slender spines and a long, mesial, slender hair. 1. NEOTANAIS AMERICANUS, n. sp. The species is represented by two specimens, both males, measuring about 7 millim. The body is elongated and everywhere of approximately the same diameter. The cephalothorax has a convex anterior margin ; on either side of the antennules are the minute, but separate, ocular lobes, which, however, show no traces of ocular structures. The thoracic segments increase in length up to the fourth, after which they diminish. The five anterior abdominal segments are subequal, the terminal segment is of course longer, it terminates in a minute, median, triangular process. The antennules consist of a three-jointed peduncle, and a four-jointed flagellum, the joints of which are very minute. In the antennae the peduncle is five-jointed, and the flagellum consists of four joints. The chelipeds are short and stout. There is no difference in size between any of the succeeding thoracic appendages, only the difference in the terminal joint referred to above. All the abdominal appendages are present; the uropoda consist of a very stout basal joint, with which are articulated the long eight-jointed endopodite and the small two-jointed exopodite. Station 45 ; 1250 fathoms. Station 323 ; 1900 fathoms. Genus LEPTOGNATHIA, G. 0. Sars. 1. L E P T O G N A T H I A AUSTRALIS, n. sp. A single female example of this species was dredged in shallow water at Kerguelen, it measures 4 millim. The body is extremely narrow and elongated. The cephalothorax is longer than the first segment of the thorax, but not so long as the first two segments; the eyes are completely absent; the first segment of the thorax is shorter than any of the three following, which are subequal, and each about half as long again as the first segment ; the fifth segment is shorter than the fourth, but a trifle longer than the first; the last segment of the thorax equals the first in length ; the first pair of thoracic appendages are articulated close to the anterior margin of their segment; the second, third, and fourth pairs at about the middle of their respective segments ; the last two pairs are articulated a very little nearer to the posterior margin. The abdomen is altogether as long as the last two segments of the thorax and one half of the fourth. The antennules are not so long as the cephalothorax, they are four-jointed. The chelipeds are stout and robust, all the joints are smooth, the distal joints are not serrated as in L. longiremis, the three anterior pairs of thoracic appendages are more slender than the posterior pairs. The rami of the uropoda are both Particulate, but the endopodite is much longer and stouter than the exopodite. Kerguelen, Christmas Harbour, 120 fathoms, |