KONGL. SV. VET. AKADEMIENS HANDL1NGAR. BAND. 22. N:0 7. 211 



is longer than broad. The tibia is longer than the genu, with the front margin smooth. 

 The carpus is much shorter than the tibia; the front margin is smooth. The meta- 

 carpus is about as long as that in the third and fourth pairs, shorter than the two pre- 

 ceding joints together, and only a little more than half as long as the femur; the front 

 margin is finely serrated. The dactylus is about half as long as the metacarpus. 



The pleon is much longer than the whole peraeon, but shorter than the head and 

 peraeon together. The first segment is longer than the last two pergonal segments together. 

 The lateral parts of the segments are almost square behind, with the angles obtuse. 



The pleopoda. The outer ramus has ten joints, the inner nine. 



The urus is not quite as long as the last pleonal segment. The first ural segment 

 is considerably longer and broader than the last coalesced, which has a very deep incision 

 on each side for the insertion of the second pair of uropoda; this last segment is more 

 than a third part broader at the base than it is long, and shows a broadly rounded pro- 

 jection at the middle of the hind margin for the support of the telson (PI. X, fig. 52). 



The uropoda (PI. X, fig. 52 — 53). The first pair reach almost to the apex of the 

 third pair; the peduncle is tolerably broad, not three times as long as broad, and only a 

 little longer than the inner ramus; the rami are elongate, sharp-pointed, and each shows 

 a deep semicircular incision (PI. X, fig. 53) at the base where they are in contact with 

 one another; this incision opens into the interior of the ramus, and is densely set with 

 short, spine-like hairs; wheter this incision is only an outlet for the secretion from the 

 glands, as I have supposed above, or wheter it contains a peculiar sensitive organ is a 

 riddle not to be solved without careful investigation of fresh material. The fact that I 

 have observed at the apex of one or more of the sharp-pointed rami in this and other 

 species a minute, circular hole or outlet, seems to make it doubtful wheter the semi-circular 

 incisions just mentioned are likely to prove to be only glandular outlets. The outer ramus is 

 somewhat shorter than the inner, smooth on the outer margin, and finely serrated along 

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

 The second pair reach to the middle of the outer ramus of the last pair; the peduncle is 

 a little more than twice as long as broad, and scarcely longer than the inner ramus; the 

 rami have the same form and serration as in the first pair, and show similar semicir- 

 cular incisions; the outer ramus is considerably shorter than the inner. The peduncle of 

 the third pair is tolerably broad, somewhat more than twice as long as broad, and a 

 little longer than the last ural segment; the inner ramus is much longer than the breadth, 

 and than half the length, of the peduncle; the outer margin is serrated, the inner smooth; 

 the outer ramus is shorter than the inner, and has the outer margin smooth, and the 

 inner serrated. 



The telson is semicircular, somewhat broader than long, and quite half as long as 

 the last ural segment; it is broader than, but not half as long as, the peduncle of the last 

 pair of uropoda. 



