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Show 106 MR. F. E. BEDDARD ON ISOPODA COLLECTED [Feb. 2, has two joints, the distal one being very minute. The antenna have a five-jointed peduncle and four- or five-jointed flagellum ; the third joint of the peduncle is longer than the two basal joints, the fourth joint is shorter than the third, the fifth longer. The thoracic appendages are all similar and biunguiculate. Off Marion Island, 100 fathoms. Genus TRICHOPLEON, nov. gen. A single specimen of a deep-sea Isopod dredged at Station 215 does not fall very conveniently within any known genus of the Asellidce. The general shape of the body is like that of Asellus, with which it also agrees in the uniunguiculate thoracic appendages ; eyes are completely absent; the first four thoracic segments are furnished on either side with a forwardly-directed lateral spine. The antennae have a movable scale attached to the second joint, as in Janira and Stenetrium. The surface of the body is quite smooth. 1. TRICHOPLEON RAMOSUM, n. sp. The specimen is an immature female, measuring 5 millim. in length. The head is narrower, but longer than the succeeding segment of the thorax; it is prolonged into a short wide process anteriorly. There is no trace of eyes. The three first segments of the thorax are subequal in length; the fourth segment is shorter; the three posterior segments gradually increase in length but diminish in breadth ; the antero-lateral margin of the first four segments is furnished with a short, acute, forwardly-directed spine. The abdominal shield is oval, but wider anteriorly than posteriorly ; it terminates behind in the middle line in a short spiny process. The antennules are about as long as the head and first two segments of the thorax together ; the peduncle has four joints, of which the second joint is the longest; the flagellum consists of about fifteen joints. The antennae are about equal in length to the body; the flagellum is longer than the peduncle ; the two basal joints of the peduncle are very short, the third a trifle longer, with an articulated scale on the outer side ; the two distal joints are long and subequal. The mandibles have a palp. The thoracic appendages are similar to each other, terminating in a single claw. Uropoda moderately long, biramose, each ramus one-jointed. Station 214; 500 fathoms. Fam. ARCTURID^E. Genus ARCTURUS, Latreille. 1. ARCTURUS MYOPS, n. sp. The present species differs from any other Arcturus at present known by the fact that the eyes are entirely or almost entirely aborted. The only trace of eyes left are a pair of rounded tubercles, which appear to contain no pigment and are not faceted. The largest |