NO. 1 BARNARD: AMPHIPODA OF THE FAMILY AMPELISCIDAE 17 



Peraeopod 3 : posterior edge of article 5 with 2 or 3 groups of spines, 

 posterior edge of article 6 with 5 to 7 spines. 



Peraeopod 4: posterior edge of article 5 with 2 or 3 groups of 

 spines, posterior edge of article 6 with 4 or 5 spines. 



Peraeopod 5 : posterior lobe of article 2, lower posterior margin 

 obliquely rounded, reaching down to junction between articles 4 and 5 ; 

 article 4 longer than 3, with a moderately strong posterior, setose lobe ; 

 article 5, anterior distal edge notched; article 6 longer than 5; article 

 7 about three fourths as long as 6. Lower edge of lobe of article 2 

 minutely crenulate. 



Uropod 1 reaching as far as uropod 2, rami subequal to each other 

 and to peduncle; both edges of inner ramus and outer edge of outer 

 ramus spinulate. 



Uropod 2 : rami shorter than peduncle, both margins of inner ramus 

 and outer margin of outer ramus spinulate, outer ramus tipped with a 

 long spine. 



Uropod 3 : rami broad, subequal in length, outer ramus narrower 

 than inner, both rami strongly setose, apex of outer ramus hooked. 



Telson: lobes evenly tapering, apices unnotched, armed with 1 to 

 7 spinules, middle dorsal surface of each lobe armed with a diagonal 

 row of 5 to 9 setae or 2 successive rows with 3 to 5 setae each. The 

 spinules at the apices may be strongly asymmetrical in number, such as 

 1 and 7, or be more symmetrical, such as 5 and 5 or 4 and 3. 



Pleon segment 3 : posterior margin slightly convex, lower posterior 

 angle broadly rounded. Dorsal surface of segment with 3 longitudinal 

 ridges which run forward on the body of the animal to include peraeon 

 segment 7, the middle carina continuing on to peraeon segment 6. The 

 integument lateral to the carinae may be folded or deeply pitted. 



Pleon segment 4: posterior dorsal surface raised into a strong, 

 saddle-shaped carina, the 2 apices of which are acute. 



Pleon segment 6: lateral ridges strongly developed. 



Material examined: Stations 209-34 (7), 468-35 (5), 580-36 (1), 

 934-39 (1), 936-39 (1), 1037-40 (1), 1965-50 (15), 2026-51 (4). 



Remarks: The armature of the telson of this species is very distinc- 

 tive, as is the shortness of the seventh article of peraeopods 1 and 2. 

 Although no males were found in the present collections, Shoemaker 

 (1916) has described them. 



The largest specimen at hand measured 18 mm in length (Station 

 1965-50). The smallest specimen exhibiting carinae on the dorsal sur- 

 face of pleon segment 3 was 9.5 mm in length. 



