REPORT ON THE CUMACEA. 25 



The branches arc about equal in length and somewhat longer than the scape, whereas 

 in the typical species the inner one is by far the longer, and the outer scarcely as long 

 as the trunk. The inner branch is composed of two distinctly defined joints, the first of 

 which is much the larger and somewhat expanded at the base, sublaminar, and armed 

 along the inner edge with a dense series of spines, some of which are more elongate than 

 the rest. The outer joint of this branch does not attain even half the length of the 

 preceding joint, and is also much narrower. It is armed with about eight spines, three 

 of which originate from the apex, the rest from the inner edge ; the apical spines being 

 by far the strongest. The outer branch is also biarticulate, but the first joint is here 

 very short, whereas the terminal joint is rather elongate, and furnished along the inner 

 edge with a row of strong ciliated seta?; from the apex four somewhat more elongate 

 setae originate, and to the outer edge about six slender spines are affixed, one of which 

 occurs at some distance from the rest, close to the apex. 



Habitat. — I found the above described specimen in examining a sample of dredged 

 mud preserved in strong spirit, and kindly sent to me by Mr. John Murray. The mud 

 was procured on January 29, 1874, off Cumberland Bay, Kerguelen Islands, from a 

 depth of 127 fathoms, Station 149h. 



Family III. Lampropid^e. 



I have seen fit to establish this family for the reception of three northern genera, 

 Lamprops, Hemilamprops, and Platyaspis, which present several peculiar characteristics 

 not found in other Cumacea, and now I am able to add another generic type from the 

 Challenger Expedition, undoubtedly belonging to the same family. The genus Chalaro- 

 stylis, established by Norman for a Cumacean from the " Porcupine " expedition, must 

 also, I think, be referred to this family, which thus at present comprises no less than 

 five different generic types. 



The most characteristic features distinguishing this family from the two preceding 

 are : — the fuller development of the antennulee, both flagella of which are distinctly 

 articulated and nearly equal in size ; the less rudimentary structure of the antennae in 

 the female; the comparatively great length of the second pair of legs; the presence in 

 the male of but three pairs of pleopoda (in one of the genera, Lamprops, the pleopoda 

 are even quite wanting); the distinctly developed telson; and finally, the slender form of 

 the uropoda, the inner branch of which is triarticulate. All the known forms belonging to 

 this family, except the one described below, would seem to be restricted to the northern 

 ocean. 



(ZOOL. CHALL. EXP. — PART LV. — 1887.) E* * 



