KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 35. N:0 5. 43 



Anteiince of the 2nd pair. B 1 with a naked Si reaching to the distal uiaTgin of 

 Ii 2. i? 2 with a plumose S reaching to the distal margin of the joint; the interiör 

 margin of the joint ends in a triangulär acute tooth. 



Second maxillipeds similar to those of C. obiusus, but B 2 somewhat lon ger. 



Nittatory legs of the 1st — 4th pairs. Re of the 1st — ord p. twice as long as Ri 



Longitudinal proportion of the 3 joints: 



Re 1. Re 3. Re 3. St. 



Ist pair 10 10 25 25 



2nd pair 10 10 35 30 



3rd pair . 10 10 30 27 



4th pair 7 5 10 30 



Se 1, 1, 3 on the 1st to 3rd p. (1, O, 1 on the 4th p.) triangulär with serrate margins. 

 St knife-like with coarsely serrate margins {teeth about 6 in 0,oi mm. on the 1st p.) on 

 the 1st— 3rd p., bristle-like on the 4th p. Si O, 1, 4 (1st p.), O, 1, 5 (2nd — 4tl] p.). 

 Ri 1 and Ri 2 of nearly equal length, both together as long as 7i/ 3 on the 1st p., but 

 twice as long on the 3d p. The exteriör margin of Ri 2 and 3 of the 1st p. ends in a 

 small apiculus, so also Ri 1 of the 3rd p. Si 1, 1, 5 (1st p.), 1, 2, 2 (3rd p.). Ri of the 

 4th p. rudimentary, with 2 plumose S. 



Meta,calanus N. Gen. 



Re and Ri of the natatory legs 3-jointed. Anterior part of the body with 5 pairs 

 of legs. Th 1 without lateral eye. Ri of the 2nd pair of legs as on the other pairs. 

 Re 3 of 2nd — 4th pairs of natatory legs with 3 well-developed Se. Their St knife-like 

 with finely serrated edges. Furca symmetrical. Anterior antenna; short (or do not reach 

 to the end of Th). 



Feiuale. First p. of antennas 17- (or 18-) jointed. Abdomen 4-jointed, with veutral 

 genital opening. Fifth p. of legs 2-jointed (no Ri; Re not jointed). 



Male. Left anterior antennas not prehensile. Abdomen 5-jointed. Fifth p. of legs 

 3-jointed (no Ri; Re 2-jointed with a terminal claw). 



Metacalanus Aurivillii n. sp. 



(Pl. IV, tig. IG — 25; Pl. V, fig. 1— Ii). 



Description of the female. Body. Length (anterior part 0,4ö, posterior part 0,i.h) 

 0,6:-i mm. Anterior part IV2 times longer than broad, with the greatest breadth at the 

 posterior part of Ce, tapering from Th 1 to the rounded front, 5-jointed. Lateral angle 

 of the last segment rounded. The front ends (laterally) in a cylindrical truncate rostrum, 

 carrying at its end 2 strong iilaments. Posterior pjart. Abdomen 4-jointed. Longitudinal 

 proportion of the joints as 3 : 2 : 4*^ 1. The third segment slightly longer than broad. 

 Furca, svmraetrical, slightly longer than bröd. Se not developed; Si tine, gernuflexed; 

 St 1 — 3 of nearly equal length, plumose, slightly longer than the abdomen. St 4 short. 



