COPEPODS OF THE WOODS HOLE REGION 453 



long and armed with plumose setae ; antennae, mouth parts, and legs 

 like those of the female. 



KEY TO THE SPECIES (FEMALES) 



1. Abdomen 3-segmented ; fused fifth and genital segments only five 



times as long as wide gracilis, new species (pk 453) 



Abdomen 1-segmented ; fused fifth and genital segments at least 



12 times as long as wide 2 



2. Second endopod segment of swimming legs with a row of papillae 



close to margin on ventral surface papillipes, new species (p. 454) 



Second endopod segment of swimming legs with an inner seta 



and without papillae on ventral surface lineata (p. 456) 



ER0YERIA GRACILIS, new species 



Plate 29 



Occwrence. — Fifty females and three males were taken from the 

 gills of the brown shark {C m^charhinus viilberti)^ July 25, 1923. One 

 female has been selected as the species type, with U.S.N.M. No. 

 56646 ; the males have been placed in a separate vial, with U.S.N.M. 

 No. 56645. Seven males were obtained from the nostrils of a great 

 blue shark {Galeus glaucus) , August 9, 1926, and 25 males and females 

 from the gills of another great blue shark the following day. These 

 sharks were captured in the fish nets on Marthas Vineyard. 



Color. — Body a uniform yellowish white without pigment. 



Fevfiale. — Carapace one-fourth wider than long ; cephalic area tri- 

 angular, the apex posterior, the base anterior and projecting in front 

 of the lateral areas. Styliform process stout, extending to the pos- 

 terior margin of the third segment, and curved inward at its tip. 

 Second, third, and fourth segments about the same length but dimin- 

 ishing in width, the fourth segment less than half the width of th^ 

 carapace. Fused fifth and genital segments much wider than the 

 three preceding segments, five times as long as wide and tapered 

 posteriorly. Abdomen less than one-seventh the length and one- 

 fourth the width of the fifth and genital segment, distinctly 3-seg- 

 mented, the segments diminishing backward. Caudal rami longer 

 than the anal segment, six times as long as wide, each tipped with 

 two long and two short setae. 



First antenna 6-segmented, sparsely armed with spines, but no 

 setae ; second antenna with a stout chela ; basal segment of maxilliped 

 long, narrow, and but little swollen, terminal claw enlarged at its 

 base and abruptly bent beyond its center. The two basal segments of 

 the first exopod without outer spines, but with inner setae, terminal 

 segment with four spines and four setae. Basal segment of endopod 

 with an inner seta ; second segment without an inner seta but with a 

 row of short spines on the outer margin ; terminal segment also with 

 a row of outer spines and with six apical and inner setae. In the 



