138 
from the side, the cephalic segment appears slightly vaulted. The forehead is decidedly truncate 
in outline. The distal end of the last thoracic segment is narrowly rounded below, then slopes 
steeply forward till it joins the almost straight dorsal line (Plate XLII, fig. 12). The rostral 
filaments are slender and of moderate length (Plate LXII, fig. 13). 
The combined length of the abdomen and furca is contained nearly four times in the 
total length of the cephalothorax, from the frontal margin to the distal end of the last thoracic 
segment. The genital segment is distinctly longer than the combined length of the next two 
segments. It is not quite symmetrical. The left side is slightly more inflated than the right. 
The ventral surface of the segment is produced near the middle into a rounded knob-like process. 
The second segment is short. It is about half the length of the third segment. The third 
segment is equal to half the length of the genital segment. The furcal joints are slightly longer 
than broad. The joints are rather shorter than the anal segment. 
The antennules are composed of twenty-five joints and extend beyond the furca by the 
last three joints. 
The exopodite of the antennae is eight-jointed. It is distinctly less than half the length 
of the endopodite (Plate XLII, fig. 15). 
The teeth on the biting edge of the mandible are arranged in three sets. The two 
inner sets are each represented by two teeth. The outer set is composed of three teeth (Plate 
SILI, tte, 16), 
The exopodite of the maxillae is furnished with six setae. Three of the setae are long 
and stout. The other three are short and very slender. 
The two pairs of maxillipedes are of the normal Augaptilus type. 
The first four pairs of feet are also of the usual Augaptilus form. 
The outer edge spine on the first joint of the exopodite of the first pair of feet extends 
to the middle of the third joint. 
The terminal spine on the exopodite of the fifth pair of feet is as long as the third 
joint. The inner edge spine on the second joint of the exopodite is comparatively short and 
straight. It extends to the base of the third inner edge spine on the third joint. 
Male unknown. ; 
This species is closely related to Augaftilus sguamatus Giesbrecht, but it can be separated 
by the difference in the proportional length of the abdominal segments and furcal joints, and 
by the exopodite of the maxillae being furnished with three long and three short setae. 
Occurrence. — One specimen was found in the plankton collected with the HENsEN 
vertical net at each of the following stations. 
Stat. 143 (1000 metres to surface). — Stat. 148 (1000 metres to surface). 
7. Augaptilus validus nov. sp. Plate XLIII, figs. 1—10. 
Female — length 8,77 mm. 
Seen from above, the body is ovate and very robust. The last thoracic segment is 
contracted posteriorly, and the distal ends are broadly rounded. Viewed from the side, the 
138 
