NO. 1 BARNARD : AMPHIPODA OF THE FAMILY AMPELISCIDAE 53 



Peraeopod 5 : posterior lobe of article 2 reaching downward to end 

 of article 5 ; article 4 nearly twice as long as article 3 ; article 5 longer 

 than 4, about as long as 6; article 7 styliform, one half as long as 6. 



Uropod 1 reaching to end of uropod 2 ; outer ramus longer than 

 peduncle, inner ramus shorter and more slender than outer, inner and 

 outer edges spinulate ; outer edge of outer ramus spinulate. 



Uropod 2: rami slightly shorter than peduncle; upper and outer 

 edges of both rami spinulate. 



Uropod 3 : rami subequal to each other ; opposing margins strongly 

 serrate, inner margin of inner ramus lined with stout spines, outer edge 

 of outer ramus with a row of setae. 



Telson extremely variable in length and shape of apices, cleft more 

 than one half its length, about as long as broad, apices of lobes rounded, 

 scalloped, armed with 1 or 2 setae. 



Pleon segment 3 : posterior edge broadly rounded. 



Pleon segment 4: dorsal surface gently upraised. 



Pleon segment 6 : tricarinate. 



Male: Differing from the female by the stouter article 2 of antenna 

 1 and article 4 of antenna 2 and the typical setal tuft development on 

 the antennal peduncles. The dorsal surface of pleon segment 4 is more 

 strongly produced; inner edge of inner ramus of uropod 3, spines not 

 as stout, and edge closely beset with plumose setae along its entire 

 length. 



Types: Holotype, AHF no. 3914, ovigerous female, 14 mm; para- 

 type, female. 



Type locality: Station 915-39, Sulphur Bay, Clarion Island, 5 fms. 



Material examined: Station 913-39 (1), 915-39 (2), 981-39 (1), 

 998-39 (1), 1130-40 (1), 1160-40 (1), 1168-40 (2), 1190-40 (1), 

 1194-40 (4), 1202-40 (1), 1229-41 (1), 1269-41 (1), 1328-41 (1), 

 1359-41 (1), 1380-41 (1), 1384-41 (1), 1386-41 (1), 1387-41 (15), 

 1388-41 (7), 1390-41 (19), 1411-41 (1), 1418-41 (2), 1780-49 (2). 



Remarks: This species is closely related to Byblis afflnis Sars 

 (1895), but is distinguishable by the larger eyes, the longer article 4 

 of antenna 2, and the more acute apices of the telson. It differs from 

 Byblis gaimardii (Kr^yer) essentially only in the deeper cleft of the 

 telson. It is not known whether the "Byblis gaimardii" cited by Holmes 

 in 1908 from Monterey, California, is the same as this species. 



The writer is not certain that this species is distinct from Byblis 

 japonicus Dahl (1944), and specimens from both areas should be com- 

 pared before a decision is made. Several small differences between the 



