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Show 112 MR. F. E. BEDDARD ON ISOPODA COLLECTED [Feb. 2, is similar ; the third and fourth segments have in addition another upon each side, placed between and behind the two lateral spines ; the margins of the epimera are prolonged into three short spines. Each of the three posterior thoracic segments has two or three long spines on either side; the epimera are large and terminate in two stout spines. The two anterior abdominal segments each consist of two portions-a narrower anterior and a smaller posterior portion ; the former is smooth, the latter beset with spines and tubercles ; on the first segment are two particularly long spines, one situated close to the ventral margin of the tergum, exactly above this is the other, which is of equal length ; on the second segment is a lateral spine of great length, but situated more dorsally ; the third segment has also a pair of lateral spines. The abdominal shield has a dorsal keel which is prolonged posteriorly into a curved spine. The whole of the dorsal surface is covered with minute pointed tubercles; the lateral region of the abdominal shield is flattened as in A. anna, &c, and terminates posteriorly on either side in a flattened triangular spine. Kerguelen, Royal Sound ; 28 fathoms. 11. ARCTURUS OCULATUS, n. sp. Five specimens of this small species were dredged in shallow water off Melbourne, South Australia. The largest measures no more than 7 millim. The most remarkable point about this species, and one which serves at a glance to distinguish it from any other recorded species of the genus, is the elevation of the eyes on to stalks as in the genus Munna. The frontal margin of the head is broad and truncated ; it is not excavated as in so many other species. The first four thoracic segments are subequal in length, they are convex posteriorly and flatter anteriorly ; the surface of these segments is quite smooth and free from tubercles or spines ; in the last three of these segments the epimera are furnished with a long spine. The posterior thoracic segments, like the anterior, possess an epimeral spine ; each of these segments has also a lateral tergal spine. Of the three free abdominal segments the first and third are furnished with a lateral spine on either side, which is absent from the middle segment. The abdominal shield is very convex, and terminates in a median dorsal spine as in so many other species ; the lateral margin of the caudal shield is beset with a series of somewhat curved spines situated at equidistant intervals, the lateral margin terminates in a longish flattened spine as in A. anna. On either side of the dorsal median line is another row of spines, which run from end to end of the caudal shield. Station 1G1 ; 38 fathoms. Family CYMOTHOIDJ;, ANUROPUS, nov. gen. Among the Isopoda dredged during the cruise of the * Challenger,' there are not many deep-sea species which present any striking differences from the Isopoda of shallow water. One of these species |