405 



rounded at the tip; urosome armed in a manner similar to that in the said 

 species. Cephalon very large, considerably exceeding in length the first 2 

 segments of mesosome combined, rostral projection a little more produced 

 than in P. cuspidata, anterior edges passing into the inferior by a rather 

 strong curve. Coxal plates scarcely differing in shape from those in the 

 latter species. Last pair of epimeral plates of metasome, however, considerably 

 more produced at the lateral corners. Eyes comparatively small, sublinear 

 in form, pigment chalky white. Antennae very slender, the superior ones in 

 female attaining nearly half the length of the body, and having the flagellum 

 4 times as long as the peduncle, accessory appendage scarcely half the length 

 of the latter and 6-articulate. Inferior antennae exceeding the superior by 

 nearly 1 /s of their length, flagellum half as long again as the peduncle. 

 Antennae in male still more elongated than in female, the superior ones 

 having, as usual, the 1st joint of the flagellum very large and densely clothed 

 with rather long sensory bristles, accessory appendage likewise much larger 

 than in female, but only composed of 3 articulations, the 4 innermost being- 

 coalesced to a very large flattened joint. Gnathopoda resembling those in 

 the type species, except that the dactylus is somewhat less dilated and 

 has the terminal spine much stronger than the others. The 2 anterior 

 pairs of pereiopoda likewise rather resembling those in P. cuspidata. The 3 

 posterior pairs, on the other hand, considerably more slender, and also more 

 densely setiferous, propodal joint in all very narrow, dactylus not nearly so 

 broad as in that species, and subulate in form. Last pair of uropoda with 

 the rami less broad, the outer one being somewhat longer than the inner. 

 Telson much narrower than in the type species, nearly twice as long as it is 

 broad at the base, and having, besides the 3 juxtaposed dorsal spinules, only 

 a single marginal one near the tip, cleft very deep, terminal lobes rather 

 narrow and bidentate at the tip, each bearing a single apical spinule. Body 

 rather pellucid, with a slight yellowish grey tinge ; ova in the marsupial pouch 

 orange-coloured. Length of adult female scarcely attaining 11 mm. 



Eemarks. Though very nearly allied to P. cuspidata, this new 



species may, on a closer examination, be easily distinguished, among other 

 characteristics, by the much more slender form of the antennae and of the 

 3 posterior pairs of pereiopoda, by the very slight subdorsal projections of 

 the last segment of metasome, and by the comparatively small, whitish eyes. 



Occurrence. I have met with this form rather sparingly in a few 



places off the west coast of Norway, as also in the Troiidhjemsfjord,'and only 

 in depths ranging from 50 to 100 fathoms. It thus would seem to be a more 

 distinct deep-water form than the type species. 



52 Crustacea. 



