COPEPODS OF THE WOODS HOLE REGION" 463 



endopods, whose end segment is more than twice as long as the basal 

 segment, and is tipped with long spines curved away from each other. 

 The fifth legs are 1-segmented, fingerlike, and each is tipped with two 

 tiny spines; the ventral plates on the genital segment are large and 

 divergent, and each carries a long seta on its inner margin near the 

 tip. Total length, 6.25 mm. Carapace and free thorax, 5 mm. long ; 

 second segment, 2.25 mm. wide. 



Remarks. — The female of this species has not been described since 

 1865 when Heller called it Nemesis 7ned4,terranea^ but it is evidently 

 the same species that had been described by Risso in 1826. A new 

 description of the female is here presented, and the male is described 

 for the first time in order that the type of the genus may become 

 better known. This male and the one belonging to the new species 

 pallida (p. 465) agree very closely and make it practically certain 

 that the specimens described as the male of the Jamaican species, 

 versicolor ^^ did not belong to the present genus but to Eudactylina. 



NEMESIS ATLANTICA Wilson 



Plate 33, a 



'Nemesis atlantica Wilson, Proc. U. S. Nat. Mus., vol. 60, art. 5, p. 60, pis. 9, 10, 

 1922. 



Occurrence. — Both sexes found on the gills of the thresher shark 

 {Vulpecula fjianna) in July, 1902, and on the gills of the dusky 

 shark {G archarhinus ohscm^s) in July, 1910, captured in the fish 

 nets on Marthas Vineyard. 



Distributio7i. — Beaufort, N. C, on gills of sharp-nosed shark 

 (Wilson). 



Color. — Body a bright yellow and nearly opaque, the digestive 

 tract and egg strings dark brown, almost black, the legs white, the 

 bases of the mouth parts tinged with a dull rust color. The entire 

 maxillipeds are sometimes bright crimson and nearly always have a 

 reddish tinge. 



Female. — Carapace elliptical, longer than wide; second, third, 

 and fourth segments the same length and width, a little wider than 

 the carapace; second segment with a distinct notch on each lateral 

 margin; fourth segment with short lobes at its posterior corners; 

 fifth segment narrower, its posterior margin 3-lobed. Genital seg- 

 ment transversely elliptical, narrower than fifth segment but nearly 

 twice as wide as long. Abdomen 3-segmented, anal segment longer 

 than two basal segments combined; caudal rami narrow spindle- 

 shaped, longer than anal segment, each with 4 short apical setae. 

 Terminal claw of second antenna bifid at tip; second segment of 



^ Proc. U. S. Nat. Mus., vol. 44, p. 238, 1913. 



