244 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
First antennae reaching the abdomen and rather slender ; the exopod 
of the second antenna is a little shorter than the endopod. Fifth 
legs shown in figure 345, rather stout and asymmetrical, the left longer 
than the right. The left exopod is three and a half, the right exopod 
only three, times as long as the respective endopods, which are the 
same length. Each exopod is tipped with three spines, the middle one 
the longest, the outer one much larger than the inner. The endopods 
are fingerlike, unarmed, and bluntly rounded at their tips. Total 
length 3.50mm. Metasome 2.80 mm. long, 1.10 mm. wide. 
Types —U.S.N.M. No. 74119; south of Lanai Island, Hawaiian 
Islands. 
Remarks.—This species may be recognized by the stout aspect and 
perfect symmetry of the entire body, the lack of lateral hooks on the 
head, the depression of the spines at the posterior end of the meta- 
some, and the shape and wide separation of the caudal rami. The 
two depressions on each lateral margin of the head are also 
characteristic. 
LABIDOCERA DETRUNCATA (Dana) 
PLATE 16, FIcuRES 192, 193 
Pontella detruncata Dana, Proc. Amer. Acad. Arts and Sci., vol. 2, p. 29, 1849. 
Pontellina detruncata Dana, United States Exploring Expedition, 1838-1842 
(Wilkes), vol. 14, pt. 2, Crustacea, p. 1148, 1853; pl. 80, fig. 7 a—-i, 1855. 
Stations 5; 9; 12; 14; 16; 18; 27; 30-82; 36; 3799; 3822; 8867; 3878; 
3901; 3980; 4009; 4010; 4011; 4190; 4611; 4615; 4617; 4619; 4635; 
4644; 4700; 4720-4728; 4725; 4728; 4731; 4735; 4788; 4740; 4741; 
4743 ; 4952; 5155; 5211; 5262; 5299; 5319; 5530; Tloilo Straits, and Sab- 
tin Island, Philippine Islands. This is the most widely distributed 
species of the genus in the Albatross plankton and was equally abun- 
dant in the Carnegie plankton. Brady reported it as moderately 
abundant in the Challenger plankton, but in the Siboga plankton Scott 
said it appeared to be rare, and it was not present at all in the Monaco 
plankton. On the other hand, it sometimes occurs by the hundreds in a 
surface tow where all the conditions are favorable. Hence, although 
widely distributed, it must be regarded as erratic in its dispersion and 
quite susceptible to unfavorable influences. 
LABIDOCERA EUCHAETA Giesbrecht 
PLATE 25, Fiaures 364, 364’ 
Labidocera euchaeta Girsprecut, Atti Accad. Lincei, Rome, ser. 4, vol. 5, sem. 2, 
p. 27, 1889; Fauna und Flora des Golfes von Neapel, monogr. 19, pp. 446, 
459, pl. 23, fig. 31; pl. 41, figs. 7, 36, 1892. 
Stations 16 ; 31; 3901; 4037; 5175; 5180; 5415. Established by Gies- 
brecht upon female specimens from Formosa Strait; it does not appear 
