368 CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. I. 2. PHRONIMID^E. 



Phronima sedentaria. 



the middle of the front margin, which is crenulated above, as well as below the tu- 

 bercle. The dactyl us is present in younger females, and is very short, in the larger 

 specimens it is wanting, and the apex of the metacarpus in there obtusely rounded. The 

 glands are highly developed in this as well as in the other pairs of perreopoda, for a 

 nearer knowledge of their structure I refer the reader to the excellent memoirs of Claus 

 and P. Mayer. 



The sixth pair reach scarcely to the middle of the carpus of the fifth pair. The 

 femur is straight, with feebly convex margins, and is about four times as long as broad; 

 the lower front corner is angular and sharp-pointed, and more or less projecting. The 

 genu is as long as broad, with the lower front corner projecting and more or less obtuse, 

 in the largest specimens it is broadly truncated. The tibia is narrower than the genu, but 

 is twice as long; the upper front corner is angular. The carpus is linear, longer than 

 the two preceding joints together, and more than half as long as the femur. The meta- 

 carpus is straight, feebly tapering towards the apex, and is quite half as long as the 

 carpus. The dactylus is minute, and sharp-pointed. 



The seventh pair are fully as long as the sixth. The femur is narrow, a little 

 broader above the middle than at the apex; the front margin is nearly straight, the hind 

 margin is feebly convex; the lower front corner projects into a sharp point; the femur 

 is more than five times as long as broad; it is a little longer than the femur in the fifth 

 pair, and a third part longer than that in the sixth. The genu is like that in the preced- 

 ing pair. The tibia is a little longer than the genu, with the upper front corner an- 

 gular. The carpus is somewhat longer than the two preceding joints together, and 

 scarcely a third part as long as the femur. The metacarpus is more than half as long- 

 as the carpus. The dactylus is minute. 



The pleon is almost as long as the whole person; the first segment is the longest 

 and is nearly as long as the last pergonal segment. The lower hind corner of each 

 segment is produced into a sharp-pointed process, which is longest in the third segment. 



The pleopoda decrease in size from the first to the third pair. The peduncle is 

 elongate-ovate, and is somewhat compressed. The outer ramus of the first pair has 

 seventeen joints, the inner fifteen. 



The urus is about as long as the last pleonal segment. The first ural segment is 

 more than twice as long as the last coalesced, which is about as broad as long, with a 

 deep emargination on either side for the insertion of the second pair of uropoda; at the 

 middle of the hind part of the segment there is a broad and deep excavation, in which the 

 telson is fixed, so that the hind margin of the telson projects only a trifle beyond the 

 hind margin of the last coalesced segment. 



The uropoda. The first pair reach to the apex of the third pair. The peduncle 

 is elongated, broader at the apex than at the base, being about seven times as long as 

 it is broad at the base; it is considerably more than twice as long as the inner ramus. 

 The rami are equal in length, elongated and sharp-pointed; the outer ramus is finely 

 serrated along the inner margin and smooth on the outer, the inner ramus is serrated 

 along the outer margin and smooth on the inner. The second pair do not reach to the 

 apex of the peduncle in the last pair, but reach beyond that in the first. The peduncle 



