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sisting of four segments. Groups of hair present 
on ventral side of third segment near distal 
margin and of anal segment. Genital segment 
little shorter than the two following combined. 
Genital protuberance protruded ventrally. La- 
teral flaps flanking the genital opening small. 
In dorsal view genital segment slightly asym- 
metrical. Proximal third of segment slender, 
distal two-thirds dilated. Segment with small 
knob on dorsal side and ridge on left side. 
First antennae broken short. First and second 
exopodal segments of first swimming foot in- 
completely separate. External spines of second 
foot long; external spine of second segment 
overreaching insertion of first spine on third 
segment; first spine of third segment reaching 
insertion of second spine, second spine over- 
reaching end of segment. Total length 7.25 mm. 
Holotype: usnm 120532. 
remarks: Euchaeta vorax is similar to E. 
gracilicauda (A. Scott). It differs, however, in 
the somewhat shorter abdomen, the asymmet- 
rical and wider genital segment and the longer 
external spines on the exopod of the second 
swimming foot. 
Euchaeta weberi (A. Scott, 1909) 
Figs. 53-59 
diagnosis: Male. Body slender, length of ab- 
domen and furca contained twice in that of the 
cephalothorax. In dorsal view cephalon triangu- 
lar anteriorly. Rostrum small, pointed down- 
ward. Head and first thoracic segment and 
fourth and fifth thoracic segments fused. 
Posterior lateral margins rounded, asymmetrical; 
left side slightly more produced than right side. 
Small spine on both sides near dorsal margin. 
Abdomen consisting of 5 segments. Genital 
segment slightly asymmetrical with small ridge 
on right dorsal side. Posterior margins of second 
to fourth abdominal segments with small spines. 
First antenna reaching beyond genital segment. 
Fifth pair of feet longer than abdomen. Right 
endopod styliform, just exceeding first segment 
of exopod in length. Left endopod 2-segmented. 
One tubercle in about middle of left first exo- 
podal segment. Second exopodal segment pro- 
longed into spoon-shaped lamella equipped 
with teeth along the distal and outer margins, 
the larger teeth being located distally. Finger- 
shaped process about as long as lamella. 
Tubercle at base of third exopodal segment 
haired. Third exopodal segment exceeding 
lamella and finger-like process in length, 
pointed at the apex, and with the usual tuft 
of hair. Small tooth present near base of finger- 
like process. Total length 6.41 mm. 
remarks: The species A. Scott (1909) de- 
scribed from the male as Paraeuchaeta tuber- 
culata was considered by Vervoort (1957:76) 
to be the male of Euchaeta weberi (A. Scott). 
Tanaka (1958) synonymized P. tuber culata 
with E. tonsa Giesbrecht. Fontaine (1967) 
transferred the males which were described as 
P. tuberculata by A. Scott and referred to E. 
tonsa by Tanaka to a new species, E. scaphula 
Fontaine. There was no male of this species in 
our samples. 
The male characterized above and presented 
as the hitherto undescribed male of Euchaeta 
weberi differs from E. scaphula mainly in the 
shape of the toothed lamella on the exopod of 
the left fifth foot, the distribution of the teeth 
on this lamella, and the presence of only 1 
tubercle on the first exopodal segment of the 
left fifth foot. E. scaphula has 2 tubercles and 
1 small spine on the first exopodal segment of 
the left fifth foot. 
Xanthocalanus pinguis Farran, 1905 
Figs. 60-62 
remarks: Two female specimens belonging 
to the genus Xanthocalanus were found at 
station 27. Their total lengths are 8.00 mm and 
8.91 mm. We are referring them to X. pinguis 
Farran, although the terminal segment of the 
fifth foot in the larger specimen is longer than 
the second segment, and the terminal segment 
of the fifth foot in the smaller specimen bears 
only 3 spines. There are 4 spines on the fifth 
foot of the larger specimen. The first antennae 
of both females consist of 24 free segments, 
with segments 8 and 9 fused, as reported by 
Tanaka (I960). The terminal part of the 
second maxilla is provided with sensory appen- 
dages of various sizes. 
Lophothrix gigas (A. Scott, 1909) 
Figs. 63-74 
diagnosis: Female. Body elongate, slender. 
Abdomen contained 5 times in cephalothorax. 
Cephalon and first thoracic segment separated 
