40 CLEVE, PLANKTON FROM THE INDIAN OCEAN AND THE MALAY ARCHIPELAGO. 



Calanopia elliptica Brady. 



(Pl. III, fig. 11—19; Pl. IV, fig. 1—2). 



(Report on the copepoda obtained by H. M. S. Challenger during tlie years 1873 

 —76, pag. 85, Pl. XXXrV, 1883. Giesbrecht Zool. Jahresb. 1896, Systematik. Vol. IX, 

 pag. 325). 



Diagnosis. The female. Al>domen 2-jointed. The 1st segment slightly shorter 

 than the second. Fifth pair of legs slightly asymmetrical, 4-jointed. L. 1,8 mm. 



The mnle. Abdomen 5-jointed. Distal part of the prehensile antenna 4-jointed, ^/s 

 as long as the proximal, Aa 18 without projecting spine. Left 5th leg shorter than the 

 right. Its B 2 with parallel margins. Re with 3 spines {Se). L. 1,65. 



Description of the female. Body in length (anterior part 1,2 posterior part 0,6) 

 1,8 mm. Anterior part elongated, inore than twice as long as broad, with the greatest 

 breadth at Th \, gradually tapering towards the (dorsally) rounded front, 5-jointed. 

 Longitudinal proportion of the joints 4V2 : IV2 : 1 : 1 : iVs. Ce without eyes; rostrum 

 bifid, with 2 strong and acute lobes. Last segment {Th4'^5) symmetrical, its lateral 

 angles acute. 



Abdomeri 2-jointed, joints of nearly equal length; genital segment 1^/2 times longer 

 than broad. 



Furca 2V2 times longer than broad, ^'U as long as Ah 3 ~ 5. Se near the end, 

 soraewhat longer than the furca. Si very faint, arising at the end of the interiör margin. 

 St 2 as long as the posterior part of the body, St 1 and 3 slightly shorter. St 4 more 

 than half as long as St 2 and IV2 times longer than Se. All St plumose. 



Antennop. of the 1st pair gently S-shaped, reach to the second joint of the abdomen, 

 17-jointed. Length of the joints in 0, 005 mm. 



Aa 2-4, 5, 6-8, 9~11, 12, 13, 14, 15-16, 17, 18, 19, 20, 21, 22, 23, 24-25. 

 15, 4, 16, 16, 7, 7, 7, 26, 26, 30, 30, 18, 16, 17, 17, 20. 



Strongest S on Aa 9-11, 14, 15-16. The ultimate joint with 2 longer and 4 shorter S; 

 the longest IV2 times longer than the joint. 



AntenncB of the 2nd pair. B 1 broader than long, with 1 plumose Si. B 2 as 

 long as broad, with 2 distal Si. Re slightly shorter than Ri. Re 1 broader than long, 

 naked. Re 2 three and a half times longer than broad. Re 3-6 uniting into a short joint 

 carrying 4 Si. Re 7 short with 1 -|- 3 plumose S. Ri 1 twice as long as broad, with 2 

 distal Si. Le with 6 long plumose S and Li with 2 long, 4 mediuinsized and 2 faint S. 



Mandible. B as long as broad, with 1, 1, 2 Si. Re and Ri as long as broad 

 and of equal length. Re 3-jointed, with 6 long, plumose »S. Ri with 2, 2, 6 S. The 

 masticatory apparatus has a median constriction on the basal part; the end is as broad 

 as the mandible and carries 5 teetli. The \'entral tooth is strong and curxed inwards, 

 separated by a, gap from the straight triangulär second tooth. The third and fourth tooth 

 with bifid tops. The 3rd — 5th teeth proximally hairy. Si small. 



Maxilla not jointed. Basal part large. Li 1 with about 12 stiff, in part hairy, S, 

 the distal of which is the longest. Li 2 with 2 stronger plumose and 1 shorter S; Li 3 



