56 THE VOYAGE OF H.M.S. CHALLENGER. 



of that species to another genus. Apart from the absence of a palp the shape of the 

 mandible is by no means unlike that of Munnopsis typica. The great length of the fifth 

 segment of the thorax is a character which at once distinguishes this species from 

 Munnopsis typica where the three posterior segments of the thorax are about equal. 

 Other points of difference will be apparent on comparing my description and figures of 

 Munnopsis australis with those of Munnopsis typicn. 



Station 147, off Marion Island, December 30, 1873 ; hit, 46° 16' S., long. 48° 27' E.; 

 depth, 1600 fathoms; bottom temperature, 34'2 F. ; Diatom ooze. 



Munnopsis latifvons, F. E. Beddard (PI. X. figs. 1-4). 



Munnopsis latifrons, F. E. Beddard, Proc. Zool. Soc. Lond., 1885, pt. iv. p. 917. 



A single female example of this species was dredged to the east coast of Japan, in 

 345 fathoms. 



It is a small species, measuring about 15 mm. in length, but unfortunately rather 

 damaged owing to the soft character of the integuments, which are but little calcified, 

 though brown and opaque, and not transparent as in the remarkable Eurycope pellucida 

 (see p. 71). 



The head is very large in proportion to the other segments ; it is as long as the first 

 three segments of the thorax taken together ; as the antennae and the antennules are 

 comparatively small at the base and widely separated, the frontal region of the head, 

 which is of course bent downwards at right angles to the rest of the head, is very 

 broad, much broader than in any other species known to me ; in Eurycope sovrsii, for 

 example, there is only a very narrow bar separating the bases of the antennae and 

 representing the frontal region of the head. The upper surface of the head has a tumid, 

 swollen appearance, and is covered with minute punctulations. 



The anterior thoracic segments appear, on a dorsal view, to be subequal in size ; the 

 lateral regions, however, increase progressively in size from before backwards, the first 

 segment being the shortest and the fourth the longest ; the dorsal portion of the 

 segments, as in so many other species, is saddle-shaped, the lateral region of the 

 segments is convex. The epimera are present though small, but are not prolonged into 

 spines as in many species of Eurycope. 



The three posterior segments of the thorax differ from the same segments in other 

 species by reason of their relative disproportion ; the first of these segments is very 

 decidedly the smallest, its antero-posterior diameter not being more than one-third of 

 either of the two remaining segments of the thorax ; this statement, however, only refers 

 to the dorsal region of the segment; laterally all three segments are of equal breadth. 

 The sixth and seventh segments of the thorax arc, as already mentioned, considerably 

 longer dorsally than the fifth, and are subequal. The surface of these segments is 



