KÖNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 35. N:0 5. 47 



Se of 1 — 3 p. 1:1:3, of the 4th p. 1:1:2, all triangulär, of nearly equal size and 

 with serrate edges. St equalling Be 3 in length (or somewhat sliorter on the 2nd and 

 3rd p.); its exteriör margin serrated (4 teeth in 0,oi mm.). Si 1:1:4 on the 1st p., 

 1:1:5 on the other p. Space between the distal and the next Si longer than between 

 the other. Exteriör margin of He hairy, especially on the 1st and 2nd p. Ri 3 of all 

 pairs longer than Ri 1, Ri 2 being the shortest. Ri 3 of the 1st p. longer than Ri 

 1 -|- 2. Se of all pairs plumose. O, O, 1. Si of the 1st p. 1, 1, .5, of the 2nd and 3rd 



1, 2, 5, of the 4th 1, 2, 4. 



5th pair of legs rudimentary, with 2 S, not reaching to the genital opening. 



Description of the nnale. Body. Length (anterior part 0,4, posterior 0,3 mm.) 

 0,7 mm. Anterior part twice as long as broad; its greatest breadth at the posterior 

 margin of Ce; 5-jointed. Ce nearly as long as the four other joiuts together, in front 

 truncate, its posterior margin gently convex. Posterior margin of Th 1 straight, of Ih 3 

 and 4 convex toAvards the front. Abdomen (incl. Th 5) 6-jointed; proportional length of 

 the joints 5:10:7:7:7:7. Anal-segment as long as broad. Furca as long as the anal- 

 segment, at least twice as long as broad. Its Se in the middle of the exteriör margin, 

 not reaching beyond the furca. St 2 the longest, ^/s as long as the abdomen. St 2 and 

 3 jointed at their bases. All St coarsely plumose. 



Anterior antennce bigeniculated, with at least 10 distinct joints. The middle divi- 

 sion with 4 and the distal with 2 joints. Small S of the 1st and 2nd joints of the 

 median division spinulose. First joint of the distal division of equal breadth throughoiit. 

 Terminal joint with a large sensorial appendage, longer than the distal division. 



Posterior antemue as in the female, but smaller. The two Se of B more appro- 

 ximate. 



Paracalanus aculeatus Giesbr. Male. ' 



(Pl. VI, fig. 1 — 10). 



Description of the male. Body. Length (anterior part 0,8 — 0,9, posterior part 

 0,-2ö) 1,1 mm. Anterior j)art 4-jointed; longitudinal proportion of the joints: 23:5:5:4. 

 Abdomen 4-jointed; longitudinal proportion of the joints 1:1:1:2. Anal-segment as 

 long as broad. Furca slightly longer than broad. 



Anterior antennoe. The left and right similar and resembling those of the female, 

 reach to the end of the furca, 23-jointed; Aa 1 and 2 and Aa 8 and 9 uniting, but 

 Aa 3 to Aa 6 separate. 



Posterioi' antennce. B 1 with 1 Si; B 2 with 2 distal Si; Be and Ri of equal length. 

 Re 1 shorter than Be 2, which is as long as Re 7 and as Re 3, 4, 5, 6 together. S: 2, 



2, 1, 1, 1, 1, 1 -|- 3. Ri 1 twice as long as Ri 2; the distal part half as long as the 

 proximal. Ri 2 with 14 5, those of Li genuflexed. 



Mandible. B 2 longer than broad, with 4 >S/. Re more proximal than Ri. Re 



and Ri of the same length and half as long as B 2. Articulation of Re incomplete. 



S of Re 6. Ri with a proximal lobus carrying 2 longer and 2 shorter S. Its distal 



end with 8 -f- 1 »S decreasing in length from the exteriör margin. 



