NEW BRITISH AMPHIPODA. 33 



the hinder nearly straight. The first joint a little longer than the side-plates, but not 

 so broad, pear-shaped, with spines at eleven points of the convex front margin, and 

 with a little serration at the top of the hind margin ; the second joint almost embedded 

 in the first ; the third much shorter than in the two preceding pairs, with spines at two 

 points of the hinder and four of the front margin ; the fourth joint shorter and narrower 

 than the third, with spines at three points of the front margin ; the fifth joint narrower 

 but longer than the fourth, with spines at two or three points of the front ; the finger 

 slightly curved, nearly as long as the fifth joint. 



Fourth permopods. The side-plates narrower and a little shorter than the preceding 

 pair, more strongly bilobed below. The first joint much longer than in the preceding 

 pair, elongate oval, the front margin with spines at eleven points, the hind margin 

 slightly serrate; the second joint rather longer than broad; the third joint similar to 

 that in the preceding pair, but larger ; the fourth nearly as long, with spines at four 

 points in front ; the fifth narrower, but as long, with spines at four points ; the finger 

 a little shorter than the fifth joint. 



Fifth permopods. Side-plates much smaller than the preceding pair, not bilobed, the 

 hind margin very convex, the front straight. The first joint a little longer than broad, 

 as long as in the preceding pair and much wider, almost all the front margin fringed 

 with spines, the hind margin roughly serrate ; the other joints nearly as in the third 

 pair, but the third and fourth joints smaller, and the finger as long as the smooth 

 fifth joint. 



Pleopods. The coupling-spines small, two in number, with two lateral teeth near the 

 reflexed apex ; the cleft spines two in number, the arms nearly equal ; the joints of the 

 inner ramus seven or eight, those of the outer eight or nine in number. 



Uropods. The peduncles of the first pair longer than the rami, with several spines on 

 the margins, the rami slender, tapering, subequal, the outer carrying three spines, the 

 inner a single one ; the peduncles of the second pair shorter than the rami, which are 

 nearly as long as those of the first pair, the outer a little the longer, armed with two 

 spines, the inner being unarmed ; the peduncles of the third pair scarcely longer than 

 broad, the rami smooth, slender, subequal, smaller than those of the preceding pair. 



Telson flanked for more than half its length by the produced sides of the sixth 

 segment, divided for more than a third of the length, the slightly indented apices not 

 quite reaching the distal end of the peduncles of the third uropods. 



Length one quarter of an inch. 



Locality. The Clyde. One specimen, female, containing eight or nine rather large 

 eggs in a forward state of development. 



From Sophrosyne murrayi, taken at Kerguelen Island, the new species' differs in 



' It is proper to mention that Mr. David Robertson, my colleague in this paper, by whom this and the othej 

 specimens described were captured, only assented to the adoption of the specific name robertsoni at my particular 

 request.— T. R. R. S. 



TOL. XIII. — PAET I. No. 5. — January, 1891, F 



