COPEPODS OF THE WOODS HOLE REGION 559 



166. Fifth legs uniramose, 3-segmented in female; in male left leg 

 uniramose, 5-segmented, right leg biramose, exopod 3- 

 segmented, endopod 1-segmented; surface (Adriatic). 



cf 9 Hypoacartia Steuer, 1915 



Fifth legs biramose in female, rami 1-segmented 167 



167 Fifth legs uniramose in male, right leg 4-segmented, left 3- 

 segmented, without a chela; fifth endopods in the female 

 reduced to spines; Antarctic plankton. 



(f 9 Paralabidocera Wolfenden, 19U» 



Left fifth leg in male uniramose, 3-segmented; right leg bira- 

 mose, exopod 2-segmented, endopod a claw; fifth endopods 

 in female conical; surface (Gulf of Manaar)_ c? 9 Acartiella Sewell, 1914 



168. Endopods of fifth legs 3-segmented in both sexes; exopods in 



female 3-segmented, middle segment with spine; left male 

 exopod 2-segmented right 3-segmented ; open ocean. 



cT 9 Centropages Ivr0yer, 1849 (p. 85) 20 



Endopods of fifth legs 2-segmented in both sexes; exopods in 

 female 3-segmented, middle segment with spine; left male 

 exopod 1-segmented, right 3-segmented; fresh water (New 

 Zealand) <^ ? Calamoecia Brady, 1906 



169. Caudal rami six times as long as wide; fifth legs 3-segmented 



in female; in male left fifth leg 4-segmented, right 3- 

 segmented, uncinate; open ocean__... d" 9 Temora Baird, 1850 (p. 103) 

 Caudal rami only three times as long as wide or less I'U 



170. Exopod of second antenna less than half as long as endopod 171 



Exopod of second antenna as long as the endopod 



171. Fifth legs in female 3-segmented, each tipped with a long seta; 



in male 4-segmented and somewhat asymmetrical, the 



right leg the longer; open ocean cf 9 Acartia Dana, 1846 (p. 159) 



Fifth legs in female 2-segmented, basal segments fused, end 

 segment a toothed claw; in male right leg 4-segmented, 

 left 3-segmented, half as long as right; open ocean. .. ,on. 



cf 9 Paracartia T. Scott, 1894 



172. Urosome symmetrical; fifth legs in female 3- or 4-segmented, 



in male 4-segmented, the two distal segments of right leg 



forming a stout chela; open ocean cf 9 Calanopia Dana, 1852 



Urosome asymmetrical; male fifth legs without a chela 17^ 



173. Fifth legs in female 2- or 3-segmented, often unequal in length; 



in male 4-segmented with a terminal claw; right leg often 



only 3-segmented; open ocean, cf 9 Tortanus Giesbrecht, 1898 (p. 166) 



Fifth legs in female 3-segmented, very small and symmetrical; 

 left leg in male 4-segmented, right 3-segmented, the 2 end 

 segments scissorlike; open ocean. _ d" 9 Candacia Dana, 1846 (p. 138) 



174. Fifth legs uniramose or lacking in female, biramose in male. 175 



Fifth legs uniramose in both sexes, in female 4-segmented, in 



male 5-segmented, without a chela; exopod of second an- 

 tenna made up of 7 segments; open ocean. 



cf 9 Eury temora Giesbrecht, 1881 (p. lU/) 



Fifth legs biramose in female, or in both sexes l<o 



«^ lu exceptional cases fusion causes the endopods of one or all the swimming legs to appear 2-segmented . 



