COPEPODS GATHERED BY ALBATROSS—WILSON 249 
The six setae on each ramus all curve inward and form a prominent 
heart-shaped terminus to the urosome. 
LABIDOCERA TENUICAUDA, new species 
PLATE 25, FIGURES 365-369 
Station 5415; [loilo Straits, Philippine Islands. Six specimens, in- 
cluding both sexes, were found in the plankton at these two localities 
in the Philippines. 
Female.—Metasome narrowed anteriorly and widened posteriorly ; 
head almost squarely truncated in front with a slight protuberance 
over the base of the rostrum and without lateral hooks. Fourth and 
fifth segments separated with small spines on the posterior margins 
of the latter. Urosome symmetrical, less than a fifth as long and about 
a sixth as wide as the metasome and made up of three segments. Gen- 
ital segment as long as the two abdominal segments combined, the 
latter equal in length but the anal segment widened. Caudal rami 
twice as long as wide, the inner margins nearly straight, the outer mar- 
gins strongly convex. 
First antennae slender, reaching the posterior end of the metasome; 
second antennae with the exopod considerably shorter than the endo- 
pod. Fifth exopods two and a half times as long as the endopods, 
each with three outer spines, one at the tip and a minute one on the 
inner margin at the base of the terminal spine; endopods with simple, 
pointed, unarmed spines. 
Male.—Metasome elongate-elliptical, narrowed at both ends. The 
posterior corners of the fifth segment are produced into slender spines, 
which are curved inward and reach the center of the second urosome 
segment. Urosome, excluding the caudal rami, one-fifth as long as 
the metasome and 4-segmented, the segments all about the same length 
and width. Caudal rami longer than the last two abdominal segments 
combined, six times as long as wide and parallel. 
Grasping (right) antenna, shown in figure 367, with a terminal por- 
tion made up of four segments, the segment next to the hinge as long 
as the other three combined and toothed along its inner margin. The 
segment on the other side of the hinge carries a long inner curved proc- 
ess, toothed on itsinner margin. In the fifth legs the hand of the chela 
on the right leg is stout and has a small thumblike process at its proxi- 
malcorner. The movable finger is hollowed on its inner side with two 
spines at the basal end of the hollow; it reaches beyond the base of the 
hand where it is curved inward and tipped with two curved setae. The 
_ second basipod of the left leg has the rudiment of an endopod at its 
inner distal corner. The two segments of the exopod are set with hairs 
cn their inner surfaces and the end segment is tipped with spines. 
Total length 1.95 mm. Metasome 1.50 mm. long; 0.65 mm. wide. 
