COPEPODS OP THE WOODS HOLE REGION 

 Genus CHIRIDIUS Giesbrecht, 1892 



47 



Head narrowed anteriorly; fourth and fifth segments completely 

 fused, with slender and sharp spines at the posterior corners. Uro- 

 some 4-segmented in female, 5-segmented in male ; caudal rami nearly 

 as wide as long; appendicular bristles short and on the ventral sur- 

 face. Exopods of first four pairs of legs 3-segmented; first endo- 

 pods 1 -segmented, second endopods 2-segmented, third and fourth 

 endopods 3-segmented; fifth legs lacking in female, uniramose and 

 5-segmented in male, often with the rudiment of an endopod. One 

 species found here. 



CHIRIDIUS ARMATUS (Boeck) 



Figure 28 



1901. 



Euchaeta annata Boeck, Forh. Vid.-Selsk. Christianla, 1872, p. 39. 

 Chmdius armatus Sars, Crustacea of Norway, vol. 4, p. 27, pis. 15, 16, 



Occurrence. — One male 

 from trawl wings, Sta- 

 tion 2230, Fish Hawk; 12 

 males and females in a 

 vertical haul. Station 

 20077, Grampus, east of 

 Cape Cod. 



Distribution. — Nor- 

 wegian coast and fiords 

 (Boeck, Sars); North 

 Atlantic (Cleve) ; British 

 seas (T. Scott); North 

 Sea (Damas and Koe- 

 foed) ; Greenland (Van- 

 hoffen). 



Color. — Body trans- 



■j . Figure 28. — Chiridiiis armatus: a. Female, dorsal 



parent and colorless, with (after Sars) ; b, fifth legs, young male ; c, fifth 



a faint wash of rosy red ; ^'^ss, aduit male (r, right leg) 

 intestine in the female bright carmine, in the male much duller and 

 more of a brick red; ovaries and oviducts opaque white; eye dark 

 ruby red (Rathbun). 



Female. — Metasome nearly three times as long as wide, the spines 

 on the posterior corners of the fifth segment short and somewhat 

 divergent. Head with a very small bifid rostrum; first antennae 

 reaching the first abdominal segment; caudal rami no longer than 

 the anal segment, and a little divergent; exopod of second antennae 

 7-segmented and one-third longer than the endopod. Total length, 

 4 mm. 



