COPEPODS OF THE WOODS HOLE REGION 381 



view. Second segment of mandibles with a large spine on its poste- 

 rior margin near the distal end; apical claw of maxillipeds trans- 

 versely corrugated. Total length, 2-2.3 mm. 

 Male . — Unknown. 



FiGDRB 235. — Tucca corpulentus: a. Female, dorsal; i, 

 female, fourth leg 



Bemarks. — This can be distinguished from the preceding species 

 by its larger size, by the fact that the trunk conceals the urosome 

 in dorsal view, and by the absence of pits on dorsal and ventral 

 surfaces. 



Genus BOMOLOCHUS Nordmann, 1832 



Body cyclopoid; head fused with first segment and enlarged, the 

 rest of the metasome tapered regularly backward; urosome 4-seg- 

 mented in both sexes; genital segment enlarged but little, lobed at 

 posterior corners in the male; caudal rami short and wide. First 

 antennae 6-segmented, the three basal segments fused in the female, 

 widened, and fringed with a row of flattened setae ; second antennae 

 4-segmented ; maxillipeds in female turned forward outside the other 

 mouth parts and more or less fused with the head, the apical claw 

 S-shaped, in the male normally placed. Endopod of first leg 3-seg- 

 mented, exopod 1-, 2-, or 3-segmented ; endopods of second, third, and 

 fourth legs 3-segmented, exopods 3- or 4-segmented; fifth legs uni- 

 ramose, 2- or 3-segmented. Both sexes parasitic on gills of fishes in 

 fresh or salt water. 



KEY TO THE SPECIES (FEMALES) 



1. Exopods of second, tliird, and fourth legs 4-segmented ; both 



rami of first legs 2-segmented; fifth leg 2-segmented teres (p. 381) 



Exopods of second, third, and fourth legs 3-segmented; both 

 rami of first legs 3-segmented ; fifth leg 3-segmented. 



albidus, new species (p. 382) 



BOMOLOCHUS TERES Wilson 



Plate 23, a, h 



BomolocJms teres Wilson, Proc. U. S. Nat. Mus., vol. 39, p. 379, pi. 59, 1911. 



Occurrence. — Many females from the gills of the common men- 

 haden {Brevoortia tyram/nus) at Woods Hole. 

 71937—32 26 



