COPEPODS GATHERED BY ALBATROSS—WILSON 161 
AMALLOTHRIX GRACILIS (Sars) 
Scolecithricella gracilis Sars, Bull. Mus. Océanogr. Monaco, No. 26, p. 21, 1905a. 
Amallothriz gracilis Saks, Rés. camp. sci. Albert de Monaco, No. 69, p. 176, pl. 
49, figs. 9-21, 1925. 
Stations 4665; 4707; 4717; 4719; 4721; 4722; 5233. Established 
by Sars as a new species of Scolecithricella in his preliminary report 
on the Monaco plankton, it was transferred in the final Monaco list 
to the present genus, which was new, and became the type species. 
It was briefly described and figured in the Siboga plankton but did 
not appear in the other lists. 
AMALLOTHRIX INVENUSTA Wilson, new species 
PLATE 3, FIGURES 9-17 
Station 4679. Fifteen females were taken at this station off Callao, 
Peru, and were identified by Sars as a new species, for which, how- 
ever, he suggested no name. His drawings, here reproduced, well 
illustrate the species. 
Female.—Metasome elliptical, considerably narrowed anteriorly 
and posteriorly and widest across the posterior margin of the cephalo- 
thorax. Head fused with the first segment, the two more than half 
the entire length; second and third segments about equal in length, 
fused fourth and fifth segments longer, with a reentrant posterior 
margin. Urosome short, less than a fourth as long as the metasome 
and about the same width throughout. Genital segment longer than 
wide and only slightly protruding ventrally, with nearly straight 
sides. Abdomen as long as the genital segment, 3-segmented, the 
segments about equal in length. Caudal rami as wide as long and 
somewhat divergent. 
First antennae reaching the caudal rami; exopod of second antenna 
longer than the endopod, the setae of both rami very long and densely 
plumose. The five basal lobes of the second maxilla are very unequal 
in size, the three terminal sensory filaments are elongate and equal 
in length, while the five filaments bearing terminal buttons are much 
shorter and quite unequal. Neither of the two basal segments of the 
maxillipeds has processes; both have setae only. The second and 
third legs are armed with spines on the ventral surfaces of the endo- 
pods as shown on plate 3, figures 16, 17. The fifth legs have the 
second segment projecting at the inner distal corner, while the termi- 
nal segment is broadly rounded at its tip and armed there with two 
minute spines. The large setose spine on the inner margin is as long 
as the segment itself and is attached behind the center of the margin. 
Total length 3.38 mm. Metasome 2.81 mm. long and 1.25 mm. wide. 
Type.—v.S.N.M. No. 70756. 
