T1O 
prominent. The lateral margins of the last thoracic segment are evenly contracted, and termi- 
nate in a short point. Viewed from the side, the crest is rather low and is broadly rounded 
at the apex. The posterior margin of the last thoracic segment is triangular in outline and 
sharply pointed. The middle of the ventral margin is distinctly pointed. The rostrum is short 
and very broad. The apical spines are very small and stout. 
The combined length of the abdomen and furca is contained fully 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 appears cylindrical when viewed from above, and is equal 
to the combined length of the next two segments. The proximal portion of the ventral surface 
is produced into a broadly triangular process. The second and third segments are of equal 
length. The furcal joints are slightly longer than broad, and are equal to about two-thirds of 
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 nearly similar to those of Scot- 
tocalanus securifrons. 
The four pairs of swimming feet are also nearly similar to those of that species. 
The free joint of the fifth pair of feet is of almost equal width throughout. The inner 
margin is slightly concave, and the outer margin is flatly rounded. The long subapical spine 
is fully four and a half times as long as the joint, and is bifid at the apex. The apical spine 
is short, and is equal to one-nineteenth of the length of the long spine. 
Male — length 6 mm. 
In general appearance it resembles the female. The crest is low and the last thoracic 
segment terminates in small points. Viewed from the side, the crest appears low and broadly 
rounded. The last thoracic segment is rather flatly rounded at the distal end, and is furnished 
with a small spine near the lower edge. The ventral margin of the segment is slightly inflated, 
and is sinuous in outline. The rostrum is moderately long and wide. It is narrower than in 
the female, and the excavation is deeper. The apical spines are also slightly longer. 
The combined length of the abdomen and furca is contained two and one-third times 
in the total length of the cephalothorax, from the apex of the crest to the base of the genital 
segment. The furcal joints are very small. 
The antennules are composed of nineteen joints, and extend to the middle of the fourth 
abdominal segment. 
The antennae, mandibles, maxillae and maxillipedes are similar to those of the female. 
The four pairs of swimming are also similar to those of the female. 
The exopodite of the right fifth foot is three-jointed and is only slightly curved. The 
third joint is moderately long and lamelliform. The endopodite is spiniform and extends to the 
end of the first joint of the exopodite. The exopodite of the left fifth foot is cylindrical, and 
the first joint is rather longer than the second. The apex of the second joint is furnished with 
two curved spines and a pad of hairs. The endopodite is lamelliform, and is only a little longer 
than the first joint of the exopodite. 
The male and female of this species are easily distinguished from the other members of 
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