252 PROCEEDINGS OF THE NATIONAL MUSEUM vol. in 



Al reaching about to posterior margin of urosome segment 2. 

 Left Al 21 -segmented, like that of female but with larger aesthetascs. 

 Eight Al 19-segmented; geniculation between segments 17 and 18; 

 segment 3 bearing 3 very long setae; segments 4-7 very short; segment 

 9 with long, heavUy chitinized spine; segments 10-11, 13-16, and 18 

 with shorter spines. Segment 17 with dentate lamella on anterior 

 margin; segment 18 with partial suture near proximal end; segment 

 19 the longest. 



Mouthparts and P1-P4 as in female. Eight P5 shghtly shorter 

 than left. Bl with 4-5 stout spines on medial margin. B2 about 

 1.6 times as long as wide; proximal part of medial margin with row of 

 4 spines posterior to which is brush of spinules ; lateral margin with a 

 few well-separated spinules. Eel wider than long; medial margin 

 bearing slender seta with globular base, produced distaUy into rounded 

 lobe bordered with spinules; anterior part of distal margin spinulose, 

 posterior part with strong lateral spine and peculiar bilobed appendage ; 

 inner lobe of appendage longer, distally spinose; outer lobe bearing 

 curved setule at apex. Ee2 about as wide as long; medial margin 

 produced in middle, where it bears a seta with angular process at base ; 

 lateral margin evenly rounded, with spine at distolateral corner. 

 Claw slightly longer than Ee2, strongly curved, produced at base into 

 bilobed process bearing seta on each lobe. 



Bl of left P5 slightly longer than wide; inner margin strongly 

 convex, armed with 2-3 heavy dentate spines; anterior surface with 

 row of 4 spines near distal margin. B2 elongate; medial margin 

 armed along most of length with brush of about 3 rows of spinules; 

 posterior sm^face with curved row of spinules bounded proximally by 

 slender seta; lateral margin with a few widely spaced setae. Lateral 

 margin of Eel with spine near distal end and seta proximal to spine; 

 medial margin with seta at distal end. Ee2 with acute apex bearing 

 minute seta; near apex are 1 lateral seta and 3 medial setae arranged 

 as shown in figures 7h-i; most proximal medial seta very small and 

 in some views hidden by larger seta distal to it. Ei about .75 as long 

 as Ee; apex and distal .4 of medial margin spinulose. 



Color. — Without pigment except for pairs of red spots on dorsal 

 surface, indicated by stippling in figure 6a; a pair at the anterior 

 margin of PedSeg 2, a pair in the middle of PedSeg 4, and pairs on the 

 posterior parts of the genital segment and urosome segment 2. 



Types.— Holotype, female, USNM 107790; allotype, male, USMN 

 107791; and 187 paratypes (46 females, 63 males, 78 copepodids), 

 from Baliia Fosforescente, Puerto Eico, collected Apr. 13, 1957. 



Distribution. — In the Puerto Eico collections, P. cokeri was taken 

 only in Bahia Fosforescente. It was collected at Marigot Bay and 

 Castries Harbor, St. Lucia, and at St. Johns, Antigua, by Smithsonian- 



