16 G. O. SARS. CRUSTACEA. [NORW. POL. EXP. 



insertion of the 2 pairs of antennae, it forms, on each side, a slight rounded 

 lobe, within which the very small eyes have their place, and below, it terminates 

 on each side in another obtuse lobe, with which the buccal mass is connected. 



The segments of the mesosome are well defined in their dorsal part, 

 exhibiting laterally an even horizontal margin, with which the extremely small 

 coxal plates are connected; but the protruding ventral part of the 2nd to 

 5th segments seems to form a continuous whole. The 1st segment is 

 rather short, scarcely exceeding in length the cephalon, whereas the 3 suc- 

 ceeding segments are of considerable size, the 3rd and 4th each exhibiting 

 in front an elevated transversal eminence defined behind by a distinct depres- 

 sion. The 3 posterior segments rapidly diminish in size; the last 2 do not 

 exhibit any protuberant ventral part, and on the whole are very similar in 

 appearance to the 3 succeeding segments belonging to the metasome. The 

 epimeral plates of the latter are comparatively small and evenly rounded. 



The urosome (see also fig. 16), as in the true Hyperiids, is depressed, 

 and composed of 2 segments only, the last 2 being wholly fused together. 

 The whole posterior division of the body, comprising the metasome and 

 urosome, scarcely attains half the length of the anterior, and this is regarded 

 by Dr. Bovallius as a distinctive character, separating the present species from 

 some of the others. It is very probable, however, that in the male this 

 division is much more fully developed than in the female. 



The eyes, contrary to what is the case in the true Hyperiids, are 

 extremely small, rounded, and composed of a restricted number of visual 

 elements, imbedded in a light red pigment. 



The superior antennae (see figs. 2, 3) issue at rather a long distance from 

 the upper angle of the head, and widely apart from each other. They are 

 apparently composed of only 3 joints, the first 2 constituting the peduncle, 

 the 3rd the flagellum. Of the peduncular joints, the 1st is the larger, and is 

 defined from the 2nd by a deep constriction. It may be tiiat, as indicated 

 by Dr. Bovallius for the type species, there is a very short intermediate joint 

 in the peduncle; but I have not been able to see such a joint with any 

 distinctness in the specimens I have examined. The terminal joint, or 

 flagellum, is somewhat longer than the peduncle, compressed, lanceolate, and 

 edged with very small sensory bristles. Any apical joints, I have failed to 

 distinguish. 



