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Show 1885.] DURING THE VOYAGE OF H.M.S. 'CHALLENGER.' 917 As in M. typica the anterior part of the body, consisting of the head and of the first four segments of the thorax, is wider than the posterior region of the thorax and the abdomen ; the first segment of the thorax is the smallest, the second is the largest and projects considerably dorsally above the general surface of the body ; the two next segments are a trifle smaller and subequal. The fifth segment is triangular in shape, very narrow anteriorly, and wider posteriorly ; it is longer than either of the succeeding segments, which are very short; the seventh is almost fused with the abdominal segment; the latter is long, with a narrow median raised area; it terminates in two minute posterior tubercles, outside of which are the uropoda. The surface of the body is smooth and devoid of spines. The mandibles have no palp. Station 168, 1100 fathoms. 2. MUNNOPSIS LATIFRONS, n. sp. A single example, female, measuring 15 millim. in length, from N. Pacific, off Japan. The head is long in proportion to the other segments ; it is as long as the first three taken together ; the first four segments of the thorax appear on a dorsal view to be subequal; the lateral regions, however, increase progressively in length from before backwards ; the segments are excavated above. The three posterior segments of the body do not differ widely in transverse diameter from the anterior segments as they do in M. typica ; their shape is more like that of Eurycope ; the first of these segments is decidedly the shortest in the dorsal region, laterally they are all subequal in anteroposterior diameter. The abdomen is rather damaged, it appears to be oval in form, and rounded off at its free extremity ; laterally, and in front of the articulation of the long styliform uropoda is a spiny process directed backwards; the antennae are of great length, measuring 87 millim. ; the flagellum is very much shorter than the last joint of the peduncle, measuring only 5 millim. The mandible has a palp. The first pair of thoracic appendages form a very distinct prehensile band ; the last three pairs of appendages are natatory and like those of M. typica. Station 232, 345 fathoms. 3. MUNNOPSIS AUSTRALIS, n. sp. The third and last species which I refer to this genus is represented by a single individual, dredged between Prince Edward's Island and the Crozets. It measures 8 millim. in length. The body has the typical form of the genus. The first segment of the thorax is very short, the second five or six times as long, and subequal with the two next. The width of the body is greatest at the second segment. The remaining segments of the thorax (5-7) are extremely narrow ; the first of those segments is very much the longest, perhaps three times as long as either of the following. |