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(Hexsen vertical net iooo metres to surface), 3 specimens. - - Stat. 184, 5 specimens. — 

 Stat. 1S5 (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 (HEXSEX vertical net 750 metres to surface), 

 6 specimens. 



5. Scoftocalauus 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 thejunction of the cephalotJiorax 

 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 cephalotJiorax, 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 Scottocalmus 

 securifrons. 



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 biturcate. 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 Hexsen 

 vertical net at Station 148, 1000 metres to the surface. 



6. Scottocalanus thomasi 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 



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