COPEPODS OF THE WOODS HOLE EEGION 



403 



genital segment with leg rudiments on its lateral margins posterior 

 to the center. Abdomen 2-segmented, the basal segment less than 

 half the length of the end segment ; caudal rami large and lamellar, 

 with convex inner margins. Total length, 2.8-3.1 mm. 



FiGDRE 249. — Caligus ruflmacula^ 

 tus : a. Female, dorsal ; 6, fe- 

 male, fourth leg 



Figure 250.— Caligus rapax: a. Fe- 

 male, dorsal ; 6, female, fourth 

 leg 



Remarks. — This species may be recognized by its color when alive, 

 and by the shape and relative proportions of the genital segment in 

 the two sexes. 



CALIGUS RAPAX Milne Edwards 



FiGxmE 250 



Caligus rapax Milne Edwakds, Histoire naturelle des Crustaces, vol. 3, p. 453, 

 pi. 38, 1840.— Wilson, Proc. U. S. Nat. Mus., vol. 28, p. 568, pi. 7, 1905. 



Occurrence. — Found upon the outside surface of the following 

 fishes: Common and 4-spotted flounders, codfish, haddock, pollack, 

 common and white hakes, lumpfish, mackerel, scup, striped bass, 

 alewife, sturgeon, sting ray, barn-door skate, big skate, common 

 skate, spiny dogfish, whiting, shad, swordfish, rudderfish, sand shark, 

 remora, cutlass fish, sand launce, northern gurnard, torpedo ray, 

 smooth dogfish, halibut, crevalle, common sculpin, and Raja eglan- 

 teria. 



Distribution. — British seas (Brady, T. Scott, Norman) ; North Sea 

 (Timm) ; Greenland (Hansen) ; North Atlantic (Brian) ; Woods 

 Hole (Eathbun, Wilson). 



Color. — Ground color pale orange, the dorsal surface irregularly 

 spotted with dark reddish brown, each spot made up of a center and 

 long radiating filaments. The spots are thickest along the margins 

 of the carapace and the sides of the genital segment and the abdomen. 



