COPEPODA FROM IFALUK ATOLL 361 



quadrangular part, of which the corners are produced in spines. 

 Between spines, which shghtly overlap following somite, border is 

 denticulated. 



Genital somite formed by partial fusion of 1st and 2nd abdominal 

 segments; line of fusion distinct dorsally. Epimeral plates laterally 

 produced, wing-shaped, that of 1st somite rounded, of 2nd caudally 

 produced in some small spines. Quadrangular median plate of 1st 

 somite with 6 teeth along free edge; that of 2nd somite very strongly 

 produced, forming on each side strong external spine and smaller 

 internal spine. In addition, there is on each side a hair near the 

 insertion of the external spine. 3rd abdominal somite as long as, 

 but much narrower than, preceding somite; epimeral plates not 

 laterally produced and with some small spinules. Armature of 

 quadrangular plate as in 2nd somite, but less strongly developed. 

 4th abdominal somite as long, and as wide, as 3rd, without quadran- 

 gular plate, but with distal margin dorsally produced in number of 

 spines, overlapping anal somite and completely covering anal plate. 

 Anal somite small, half as long as 4th, anal flap invisible. 



Fm-cal rami slightly longer than broad (proportion 5:4), slightly 

 diverging. Internal and external borders smooth. There are 5 

 marginal setae and 1 appendicular seta, the position of which appears 

 from figure 142a; 2nd seta on each side is lengthened, reaching ji body 

 length, and bluntly pointed. 



Antennules (fig. 142a) slender, % length of cephahc somite, 6- 

 segmented: segments 2 and 3 long; segment 4 with small conical 

 process, bearing aesthetasc and 2 fine setae; segment 1 without spines 

 but with haired tubercle. 



Antenna (fig. 146c) with short, unsegmented exopodite, bearing 4 

 strong setae. Endopodite with 7 marginal setae and 2 spines. 



Mandible and maxillule heavily damaged in my preparation. 

 MaxiUa (fig. 146c?) with 3 endites; praecoxal and coxal endites small, 

 each with 2 setae. Basal endite better developed, with big, curved 

 spine, coalescent with endite. In addition, there is a fine seta; 

 endopodite represented by 2 setae. 



Maxillipede (fig. 146e) with long and slender coxa. Basis elongate, 

 internal border straight, external border slightly swollen. Endopodite 

 represented by single, slender digit, curved at apex and longer than 

 basis. No additional setae on endopodite. 



Leg 1 (fig. 143a) very long and slender, brought about by great 

 length of basis. External margin of coxa haired; internal and external 

 margins of basis haired; in addition, there is a seta at the external 

 basal margin. Exopodite very small, 2-segmented, both segments of 

 equal length, 2nd with 5 appendages. 1st endopodal segment 4 times 



