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Five females apparently belonging to this species were obtained from the plankton 
collected with the HENsEN vertical net at the following two stations. 
Stat. 148 (1000 metres to surface), 2 specimens. — Stat. 230 (2000 metres to surface), 3 specimens. 
The ‘Siboga’ specimens appear to be rather more robust than those obtained by Farran 
from the deep water off the West of Ireland. The rami of the rostrum are very robust and 
terminate in a slender filament. The filament is articulated at the base. The fifth pair of feet 
is almost identical with Farran’s figure. The outer edge spine is nearer the apex of the joint, 
however, than is shewn by Farran. Length 3,24 mm. 
12. Scolectthrecella gracilis Sars. Plate XXXI, figs. 1o—18. 
Scolecithricella gracilis Sars, 1905(a), p. 21. 
Two females of a form that appears to be identical with the preliminary description 
given by Sars of the above species, were found in the plankton collected with the Hernsen 
vertical net at Station 148, 1000 metres to the surface. 
This species is easily identified by its slender body and moderately long abdomen, by 
the antennules extending beyond the furca, and by the structure of the fifth pair of feet. Each 
foot is composed of a single piece, without any demarkation between the basal part. The basal 
portion of the foot is furnished with two transverse rows of small spines, which distinguishes 
the species from any other member of the genus. The inner marginal spine is nearly as long 
as the whole foot. The apical spine is fully one-third of the length of the inner spine. The 
spines are fringed with short spinules. The ‘Siboga’ specimens are furnished with a small outer- 
edge spine near the middle of the foot (Plate XXXI, fig. 18). 
. Length of female 4 mm. Male unknown. 
The fourth and fifth thoracic segments of the ‘Siboga’ specimens of this species appear 
to be indistinctly separated. 
Daly thriges™: 
Wee Scolecithricella tydemant nov. sp. Plate XXX, figs. 10o—17. 
Female — length 5,7 mm. 
Seen from above, the body appears elongate and moderately robust. The head is fused 
with the first thoracic segment, and the combined length is nearly twice that of the next four 
thoracic segments. The fourth and fifth thoracic segments are completely separated. The last 
thoracic segment is produced and apparently pointed. Viewed from the side, the forehead is 
evenly rounded and produced into a moderately long rostrum. The last thoracic segment is 
somewhat truncate at the apex and the margin is slightly emarginate. The rostrum is composed 
of two rather short and moderately stout filaments attached to a projection of the forehead. 
Each filament is distinctly bifurcate at the apex. (Plate XXX, fig. 13). 
The abdomen is short and composed of four segments. The combined length of the 
abdomen and furca is contained three and a half times in the total length of the cephalothorax, 
from the frontal margin to the base of the genital segment. The genital segment is as long as 
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