109 
(HENSEN vertical net 1000 metres to surface), 3 specimens. — Stat. 184, 5 specimens. — 
Stat. 185 (HENSEN vertical net 1536 metres to surface), 4 specimens. — Stat. 230 (HENSEN 
vertical net 2000 metres to surface), 3 specimens. — Stat. 243 (HENSEN vertical net 1000 
metres to surface), 3 specimens. — Stat. 276 (HENSEN vertical net 750 metres to surface), 
6 specimens. 
5. Scottocalanus longispinus nov. sp. Plate XXV, figs. 10—18. 
Female — length 4,75 mm. 
Seen from above, the body appears elongate ovate and moderately robust. The anterior 
and posterior ends are equally contracted. The greatest width is at the junction of the cephalothorax 
with the thoracic segments. The crest is high and conspicuous. The posterior margins of the 
last thoracic segment are produced into broadly triangular processes with a pointed apex. Viewed 
from the side, the crest is seen to have a distinctly angular apex. The last thoracic segment 
terminates in a sharp point, and the proximal portion of the ventral margin is inflated. The 
rostral points are stout and their length is equal to half the depth of the excavation. 
The combined length of the abdomen and furca is contained three and a half times 
in the total length of the cephalothorax, from the apex of the crest to the base of the genital 
segment. The genital segment is distinctly longer than the combined length of the next three 
segments. The segment appears nearly cylindrical when seen from above, but when viewed 
from the side the dorsal and ventral surfaces are distinctly gibbous. The second segment is 
nearly as long as the combined length of the next two segments. The furcal joints are longer 
than broad and are equal to the length of the second abdominal segment. 
The antennules are composed of twenty-four joints and extend a little beyond the furca. 
The antennae, mandibles, maxillae and maxillipedes are similar to those of Scottocalanus 
securtfrons. 
The four pairs of swimming feet are also similar to those of that species. 
The inner margin of the free joint of the fifth pair of feet is sharply concave near the 
middle. The apex of the joint is dilated. The long subapical spine is fully four times as long 
as the joint, and the distal end is_ not bifurcate. The apical spine is very short, and is only 
equal to one-twenty-seventh of the length of the long spine. 
Male unknown. 
This species is easily separated from the other forms, by the broadly triangular termi- 
nations of the last thoracic segment, by the short almost cylindrical abdomen, and by the length 
of the spines on the free joint of the fifth pair of feet. 
Occurrence. — One specimen was found in the plankton collected with the HENsEN 
vertical net at Station 148, 1000 metres to the surface. 
6. Scottocalanus thomast nov. sp. Plate XXVI, figs. 1—10 (female). Plate XXVIII, 
figs. 10—17 (male). 
Female — length 5,8 mm. 
Seen from above, the body is elongate ovate, but is rather less robust than in the 
previous species. The outline of the forehead is sharply triangular and the crest is not very 
10g 
