COPEPODS OF THE WOODS HOLE REGION 303 



on the inner margin near the distal end, the terminal claw is stout 

 and without accessory bristles. 



The endopod of the first legs is longer than the exopod, its two 

 basal segments unarmed except for an inner fringe of spinules, its 

 distal segment with two apical pectinated spines and a filiform seta 

 and two inner plumose setae. The middle segment of the first exopod 

 is the only one with an inner seta, the end segment has one outer and 

 three apical spines, the latter pectinated on the outer margin and 

 plumose on the inner. The rami of the second, third, and fourth legs 

 are about equal in length, all three segments of both rami carry inner 

 setae, and the end segments are tipped with a pectinated spine and 

 two plumose setae. The outer margins of both rami in the four pairs 

 of legs are fringed with rather coarse spinules. The segments of 

 each fifth leg are fused into a small lamina, separated into two lobes 

 at the distal end by a deep incision, the narrower inner lobe repre- 

 senting the basal expansion and armed with three minute spines, the 

 longer outer lobe representing the distal segment and armed with 

 five small spines. A long filiform seta on the outer margin near its 

 base represents the outer process of the basal segment. Total length, 

 0.38-0.42 mm. 



Mode. — A little larger and stouter than the female, the epimeral 

 plates not so prominent at the posterior corners of the segments. 

 Cephalic segment, excluding the rostrum, one-third the body length ; 

 rostrum wide and one-third the length of the cephalic segment. 

 Urosome broad and 3-segmented; genital segment partially divided; 

 anal segment one-half longer than the penultimate segment and 

 highly vaulted as in the female; caudal rami twice as wide as long, 

 with the usual armature ; apical setae about half the body length. 



First antennae considerably enlarged and strongly geniculate, with 

 very obscure segmentation. The second and third segments much 

 swollen and with the three terminal segments forming a regularly 

 tapered cone, pointing diagonally backward and heavily armed with 

 setae and pectinate spines. Second antennae, mouth parts, and swim- 

 ming legs like those of the female without sexual modifications. The 

 segments of each fifth leg are fused into a small semicircular lamina, 

 which is not lobed as in the female but entire and armed with four 

 plumose setae, the inner one very minute, the other three about equal. 

 At the base of this lamina on the outside is a regular outer basal 

 process, tipped with a filiform seta. The process points forward at 

 first, then turns sharply in a half circle and points backward along 

 the outer side of the lamina. Total length, 0.4-0.44 mm. 



Remarks. — This species may be recognized by its small size, by the 

 prominent epimeral plates in the female, by the large rostrum, and 



