COPEPODA 



183 



The anterior surface of the labruin has on each side, posteriorly, an area covered with fairly 

 long hairs; this group is almost fused with a transverse row of rather short hairs, which, without 

 interruption, is continued from right to left. The oral surface has in the lateral group 40—50 short 

 spine-like hairs placed in a curved row; in the middle two distinct transverse rows, as seen in fig. 9 a. 

 The groups I— II, in the longitudinal series, meet as in Euc. norv. under an angle; the groups 

 III— IV have a smooth area in the middle, while the groups V— VI are compact The groups of hairs 

 in front of the lamina labialis are in most respects like fig. 3 b, but the lateral posterior group is more 

 elongate, and consists of fewer hairs. 



Remarks etc. Of this species I have only examined a single female, taken ^4/^ 1896 St. 118 

 68°27 Iv. N. 8°20 Iv. W. Closing net 1030 fathoms by the Ingolf Expedition; it is probably nearly related 

 to E. barbala, but differs distinctly from it by the deep genital protuberance. 



55. Euchaete bisinuata G. O. Sars. 

 (PI. VI figs II a— e; text-figs 54 a— j). 



1907. Eucheete bisinuata u. sp. G. O. Sars, p. 12. 



1908. — — G. O. Sars. Farran, p. 45, pi. Ill figs 



17—19. Pl- IV fig. 4- 



1909. Euchsete bisinuata G. O. Sars. A. Scott, pp. 70—71, pl. 



XVI figs 10—17. 



Description, f?. Size: 5-62 ram.; anterior division (2-58 -(- 1-59) == 4-17; urosome 1-45 mm. Sars' 

 specimens measured 5-2 mm.; Scott's 5 mm. 



The anterior division, which is distinctly twice as long as the urosome, is rather short and 

 clumsy with the lateral corners regularly rounded. 



The genital somite is, seen from above, slightly asymmetrical with a well marked convexity 

 in front, somewhat behind the base of the somite (text-figs 53 a— c). The ventral outline shows 3 

 characteristic lobes, as figured by Farran and ScotL The posterior border of the vulva is formed 

 by a transverse, somewhat hollowed, ridge, which is gradually sloping forwards. In front of this, and on 

 each side are a median and an anterior laminous process, of which the latter is the longer and thinner; the 

 processes on the left side are comparatively shorter, and are placed more posteriorly; in ventral view they 

 are seen to be turned towards the middle, thus partly covering the vulva. The third and fourth somites 

 are almost smooth, and without any hairs below, in contrast to the fifth somite, which has ventrally a 

 tuft of hairs; it is dorsally almost completely covered by the preceding tergite. The subapical seta is 

 thinner but not very much longer than the St. 2, and it is not geniculated. 



The antenmdae extend almost to the tip of the anterior part; they are in the main like E. norv., 

 but the segments 240^25 are just as long as segment 20, and 23 is a little longer than 16, which is as 

 long as 17. The antennae and mandibulae do not show any features of interest. The Le i of the inax- 

 iUulac bears 6 bristles of almost equal width basally, but the distal bristle is much shorter than the others, 

 which are much longer thau tlie breadth of the maxillulae. The Li i has the usual 10 hairs anteriorly, 

 but only two posteriorly; the Li II as well as Li III is well developed, and each bears a long seta. The 

 basipodite III has 3 setae with short hairs, of which the distal is the longest. The Ri I has 2 rather 

 slender and a single powerful seta, while the Ri II >= III have 4 powerful ones. The convexity of the 

 exterior margin in the basal segment of the maxillae is just indicated (text-fig. 54 d). The /^j / has 



