NO. 3573 COPEPODS — HUMES AND HO 3 



to innermost distal seta 23/i, along outer edge to base of lateral seta 

 23/i, and to base of outermost distal seta 33/i. Of the usual 6 setae, 

 outer lateral seta naked and 66/x long; remaining 5 feathered: pedi- 

 cellate dorsal seta 47/x, innermost distal seta 115ju, outermost distal 

 seta 91 11, and the 2 long median terminal setae, both "pegged," 

 169;u (outer) and 200m (inner), and inserted between dorsal (unorna- 

 mented) and ventral (with marginal row of spinules) flaps. In 

 addition, a minute hyaline setule dorsally near insertion of outermost 

 distal seta. Two hairs on dorsal surface of ramus. 



Dorsal surface of prosome and dorsal and ventral surfaces of 

 urosome with a few minute hairs. Ratio of length of prosome to that 

 of urosome about 2.1:1. 



All ovigerous females observed with broken egg sacs (one shown 

 in fig. 5) . 



Rostral area (fig. 6) moderately well formed. At level of bases of 

 second antennae a small longitudinal sclerotized ridge between rostrum 

 and anterior part of labrum. 



First antenna (fig. 7) 7-segmented, with third segment showing 

 ventrally a proximal sclerotized area suggesting an intercalary seg- 

 ment. Lengths of the segments, measured along their posterior 

 nonsetiferous margins: 28^1 (56ai along anterior margin), 95^, 25/x, 50m, 

 50/i, 37m, and 22m, respectively. Formula for armature: 4, 13, 6, 3, 



4 + 1 aesthete, 2 + 1 aesthete, and 7 + 1 aesthete. All setae naked. 



Second antenna (fig. 8) 4-segmented, with last segment moderately 

 elongated, 65m along its outer edge, 39m along its inner edge, and 27m 

 wide. Each of first 2 segments with a small inner seta, third segment 

 with 3 setae (1 of them jointed), and last segment with 7 elements: 



5 setae and 2 unequal recm-ved claws 45m and 34m long (measured along 

 greatest axis). All setae naked. 



Labrum (fig. 9) with 2 relatively short posteroventral lobes, free 

 border of each lobe showing 2 small hyaline lamellae. 



Mandible (fig. 10) with its basal region bearing on its posterior 

 surface a small sclerotized area and separated by a constriction from 

 its distal region, whose inner margin bears a prominent sclerotized 

 pointed toothlike process followed by a striated fringe, whose outer 

 margin has a row of slender spinides and which terminates in a long 

 flagellum with lateral spinules. Paragnath (see fig. 9) a small lobe 

 bearing inner hairs. First maxilla (fig. 11) a single segment bearing 

 2 terminal setae. Second maxilla (fig. 12) 2-segmented, first segment 

 unarmed, second segment produced distally and bearing row of 4-5 

 teeth (compare figs. 12 and 13) and slender naked terminal process. 

 (If 4 such teeth, distalmost often slightly bifurcated; if 5, teeth all 

 entire.) On postero-inner surface of second segment 2 setae, one 

 finely pectinate along one margin, other bearing long bluntly tipped 



