246 CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. I. 2. HYPERIIDJE. 



Hyperiella antarctica. 



The sixth and seventh pairs (PL XI, fig. 50) are scarcely two thirds as long as the 

 fifth, and considerably shorter than the third and fourth pairs'. The femur has the same 

 form as in the fifth pair, with the lower front corner scarcely produced. The genu is 

 about as long as broad, with the lower front corner squared. The tibia is nearly twice 

 as long as the genu; the lower front corner is scarcely produced. The carpus is longer 

 than the tibia; the front margin is smooth. The metacarpus is a little narrower, 

 but scarcely longer, than the carpus, and much shorter than the femur; the front margin is 

 smooth. The dactylus is not fully a third part as long as the metacarpus, and is smooth. 



The pleon is as long as the last six pleonal segments together; the lateral parts 

 are rounded below and behind, with a small tuberculous prominence at the middle of the 

 under margin. 



The pleopoda. The coupling spines are hook-shaped, with three sharp teeth 

 between the apex and the base. The cleft bristle has the apically dilated arm shorter 

 than the other. The outer ramus of the first pair of pleopoda has eleven joints, the 

 inner nine. 



The urus is as long as the last pleonal segment; the first segment is considerably 

 longer than the last coalesced, which is fully twice as broad as long. 



The uropoda (PI. XI, fig. 51). The first pair reach beyond the middle of the third 

 pair; the peduncle is about four times as long as broad, and a little longer than the inner 

 ramus; the rami are elongate-lanceolate, the outer shorter and narrower than the inner; 

 the outer ramus is serrated along the inner margin, with unequal teeth; the inner ramus 

 shows a serration consisting of equal, sharp teeth along the outer margin. The second pair 

 reach almost as far as the first; the peduncle is broader below than at the base, a little 

 more than twice as long as broad at the apex, and quite as long as the inner ramus; 

 the inner ramus is elongate-ovate, serrated on the lower parts of both margins; the outer 

 ramus is elongate-lanceolate, shorter than the inner, and serrated along the inner margin. 

 The peduncle of the third pair is about three times as long as broad, with the lower 

 inner corner somewhat projecting; the inner ramus is ovate, serrated on both margins, 

 and not fully half as long as the peduncle; the outer ramus is a little more than half 

 as broad as, and somewhat shorter than, the inner; the inner margin is serrated. 



The telson is triangular, with curved margins, and two thirds as long as the last 

 ural segment; it is narrower than, and not a third part as long as, the peduncle of the 

 last pair of uropoda. 



