mal exopodal segment. The second exopodal 

 segment is like an elongated spine, enlarged 

 at its base and acuminate at the tip. The left 

 fifth leg has a much stouter basipod, a 3- 

 segmented exopod, and a rudimental endopod. 

 Three projections arise from the mediodistal 

 corner of the second exopodal segment, and 

 two of them have a row of teeth along the 

 margin (figs. 21 and 22). The third exopodal 

 segment is tapered distally into a slender spine; 

 the proximal portion of the segment is hollow 

 along the internal margin, which is fringed 

 with long hairs ; at the di.stal end of the hollow 

 portion is a small knob, which has a few 

 slender spines. 



Remarks 



Tanaka (1958) considered Euchaeta acuta 

 var. pacifica, established solely on the male by 

 Esterly (1911), synonymous with E. media. 

 Esterly's description of the fifth pair of legs 

 (the only structure described) however, seems 

 too brief for a positive identification of the 

 form. 



Euchaeta puhera Sars, 1907 



Occurrence 



Sta. 5. 1 adult female, 3.84 mm. 



Sta. 7. 3 adult females, 4.32 to 4.41 mm. 



Remarks 



The female is well characterized by the 

 evenly rounded posterolateral corners of the 

 metasome ; the symmetrical genital segment, 

 which in dorsal aspect is equally swollen on 

 each side; and the hooklike process at the right 

 side of the genital orifice. The posterior part 

 of the body is covered with fine hairs. 



Euchaeta wrighti, new species 

 (Plate 7, figs. 23-26; plate 8, figs. 1-3) 



Occurrence 



Sta. 3. 1 adult female, 2.73 mm. 



Description of Female 



The proportional lengths of the prosome and 

 urosome are about 2:1. The general shape of 

 the body is slender (plate 7, fig. 23). The 

 cephalosome and the first metasomal segment, 

 as well as the fourth and fifth metasomal seg- 

 ments, are fused, but a line of fusion between 



the cephalosome and the first metasomal seg- 

 ment is cleai-ly visible after staining. The fore- 

 head in both dorsal and lateral view is pro- 

 duced into a process, which carries a sensory 

 hair (plate 7, fig. 24). The rostrum is strong, 

 pointing straight downward. The posterolateral 

 margins of the metasome are smoothly rounded. 



The urosome is 4-segmented; the segments, 

 with the caudal rami, have the following pro- 

 portional lengths, from anterior to posterior: 

 44:22:17:6:11. 



The genital segment (plate 7, figs. 25 and 26) 

 is long and slender. In dorsal aspect it is al- 

 most perfectly symmetrical — equally swollen on 

 both sides. At about one-third the length from 

 the proximal end it has a large genital swelling 

 clearly visible in lateral aspect. The distal por- 

 tion of the metasome and the whole urosome 

 are densely covered with very fine hairs. 



The antennule is 23-segmented, and, when 

 fully extended, reaches as far as the end of the 

 caudal ramus. The maxillule is best described 

 by reference to plate 8, figure 1. In the maxilla, 

 one of the 6 apical setae has long spines, in 

 addition to short spinules that cover it entirely. 



The basipod of the first leg (plate 8, fig. 2) 

 is fringed with hairs along the internal margin 

 and has the customary curved seta on the distal 

 medial end of the basis. The exopod is 2-seg- 

 mented. The external margin of the first seg- 

 ment is almost straight and has a fine spine 

 near the di.stal end; the internal margin has a 

 single seta. The second segment has a fine 

 external spine, 3 internal setae, and 1 terminal 

 spine, which is about four times as long as the 

 segment. The endopod is a single segment ; its 

 external margin has a round tubercle armed 

 with a row of fine spinules, the internal margin 

 has 3 setae, and the apex 2 setae. 



The coxa of the second leg (plate 8, fig. 3) 

 has a row of hairs and a strong seta on the 

 interna! margin. The exopod is 3-segmented, 

 with relatively small external spines. Of these 

 spines the one on the second segment is the 

 largest, but it does not reach as far as the 

 base of the first external spine of the third 

 segment. The terminal spine of the exopod is 

 about as long as the third exopodal .segment. 

 The endopod is a single segment and is slightly 

 shorter than the first 2 exopodal segments 

 combined. 



552 



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