ART. 22 STEGOCEPHALID AND AMPELISCID AMPHIPODS SHOEMAKER 17 



Peraeopod 5 proportionally much as in H. tubicola^ but the arrange- 

 ment of spines and setae is different; both the hind margin and 

 inner surface of the posterior lobe of the second joint are thickly 

 set with long plumose setae, the lower margin of the third joint 

 bears a row of short, stout spines, the fourth joint bears in addi- 

 tion to the stout lateral spines a short row of stout spines on the 

 lower margin, the fifth joint is broader and the lateral spines longer 

 and stouter than in H. tubicola, the sixth joint bears a row of long 

 slender spines on lower distal half of front margin, the seventh 

 joint is two-thirds the length of the sixth and bears two long, slender 

 terminal spines. The lower lateral margin of pleon segment 3 

 slightly convex, the lower angle very little produced, and the lower 

 margin slightly convex and fringed with plumose setae. Uropod 

 2 projecting backward slightly beyond 1, but much less than 3. 

 The peduncle of uropod 1 is a little longer than the rami, the outer 

 of which is slightly longer than the inner. The relative propor- 

 tion of these rami is somewhat variable, in some specimens the in- 

 ner ramus is very nearly as long as the outer, while in others it is 

 decidedly shorter. The outer edge of the peduncle of uropod 1 is 

 without spines except for a single terminal one, but the inner edge 

 bears spines on the distal half; the outer ramus bears three spines 

 on the proximal half of the inner edge, but none on the outer edge ; 

 the inner ramus bears many spines on inner edge and four on proxi- 

 mal half of outer edge. In uropod 2 the outer ramus is shorter 

 than the inner and bears on the outer edge a row of closely set stout 

 spines, each of which bears a setule near the apex, the inner edge 

 bears a more sparsely set row of spines; in the inner ramus the 

 arrangement of spines is reversed, the inner edge bearing the closely 

 set row and the outer the sparsely set row. Uropod 3 has the rami 

 equal in length, foliaceous, and very bluntly rounded terminally; 

 the outer ramus bears a closely set row of plumose setae on the outer 

 and inner edges and the distal extremity, and this extremity also 

 bears a short, stout, blunt spine, which is clothed with short setules ; 

 the inner ramus bears a closely set row of plumose setae on the dis- 

 tal half of the inner margin and the distal extremity, the inner 

 margin bears three short stout spines on the distal half and a row 

 of short plumose setae on proximal half. The telson is much like 

 that of H. tubicola except that there are two plumose setules near 

 the center of the lateral margins. 



Length of the largest specimen is about 19 mm. 



Type.—V.^.'^M. No. 62831. 



Locality.— Location 106-8, steamer Speedwell, 44° 01' N., 63° 20' 

 W., about 2934 miles S. from Chebucto Head, September 20, 1877, 

 110 fathoms, fine sand and mud. 



