NO. 1 BARNARD: AMPHIPODA OF THE FAMILY AMPELISCIDAE 37 



Remarks: This species is closely related to Ampelisca brevisimulata, 

 new species, but differs in the shape of pleon segment 3, the presence of 

 a notch on article 5 of peraeopod 5, and the shape and armature of the 

 telson. 



It is also closely related to A. pacifica Holmes, but may be distin- 

 guished by the shape of uropod 3, by the notch on article 5 of peraeopod 

 5, by the shape of uropod 1, and by the armature of the telson. 



Ampelisca hancocki, new species 

 Plate 26 



Description of female: Head not as long as first 3 body segments, 

 anterior edge moderately incised, lower front edge oblique, nearly 

 straight. Eyes large, upper pair situated rather far behind the anterior 

 edge of the head, lower pair slightly below lateral angle of head. 



Antenna 1 not reaching end of peduncle of antenna 2 ; article 2 of 

 peduncle almost twice as long as article 1 ; article 3 as long as article 1. 



Antenna 2 about three fourths the length of the animal; article 5 

 of peduncle subequal in length to article 4. 



Mandible : spine row with 7 or 8 spines ; article 3 of palp about three 

 fourths as long as article 2. 



Maxilla 1: outer plate with 10 spines; palp article 2 broader than 

 outer plate, armed with 4 spines, 3 cusp teeth, and 8 setae. 



Maxilliped : inner plate slender, truncate, armed with a single chisel- 

 like tooth ; inner margin of outer plate with 6 chisel teeth, rounded apex 

 with 4 spines and 2 plumose setal spines; inner setal row with 5 setae. 

 Palp normal. 



Coxae 1 and 2 with a small slit at the lower posterior corners. 



Gnathopod 1 moderately stout ; article 6 nearly as long as article 5 ; 

 article 7 strong, two thirds as long as article 6. 



Gnathopod 2 slender ; article 6 about two thirds as long as 5 ; pos- 

 terior edge of article 6 very slightly convex ; article 7 short. 



Peraeopod 1 : article 2 stouter than article 4 ; article 7 slightly longer 

 than articles 5 and 6 combined; article 4, distal anterior edge produced 

 slightly. 



Peraeopod 2 similar to peraeopod 1 but with generic differences. 



Peraeopod 3 moderately stout; anterior edge of article 2 heavily 

 setose, with 2 spines on posterior edge ; article 5 with 1 spine on posterior 

 edge. 



Peraeopod 4: article 5 with a single spine on posterior edge, article 

 6 with 3 spines on posterior edge. 



