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cross-shaped very small area. Close behind the peduncle of the disk, the lateral margin of 
the elongated front is provided with a low. longitudinal keel (fig. 3h, y), which bears a row 
of rather short setaceous processes. The antennule are short, without distinct articulation, 
very sinuous in outline, and most sparingly provided with set; one of these is a peculiar 
olfactory seta, placed at some distance from the apex, on the posterior side. Antenne 
wanting. Mouth-border rather narrow. Maxillule somewhat larger than in the female , 
without additional branch. Maxille small and constructed like those of the female, except 
the third joint, which is pointed. Basal joint of the maxillipeds long and somewhat slender, 
on their anterior side proximally decorated with areas and rows, partly of minute prickles, 
partly of very short hairs, distally provided with several transverse rows of somewhat longer 
hairs; second and third joints coalescent, last joint essentially as in the female. The sub- 
median skeleton with the two first pairs of processes conspicuous; the first pair (i) of medium 
size, triangular and situated a little behind the base of the maxillse; the second pair (j), which 
are placed inside the base of the maxillipeds, are moderately long, shaped like narrow cones 
and strongly diverging. The lateral margin of the head essentially like that of the species 
which live typically on Amphipoda; in its whole length, from a point somewhat in front of 
the base of the antennula, furnished with long hairs; off the base of the maxilla, and before 
reaching the posterior end of the lateral margin, the outline of the hair-coat runs upward 
and slightly forward on the side of the animal till, on the middle of the side, it turns 
backward, then again continuing straight upward across the back, in a line with the posterior 
end of the lateral margin (fig. 3i). Sides and back of the trunk closely covered with 
proportionally long hairs; the central and posterior part of the ventral surface covered with 
hairs of medium length, while basally, and for a part, sub-laterally, it is quite or almost 
naked. Trunk-legs and caudal stylets altogether wanting. 
OVISACS. They are middle-sized in proportion to the females, but here I have 
met with the peculiar fact that the smaller ovisacs with few eggs, represented in fig. 3e, 
have been laid by the small female drawn in fig. 3a, whereas the larger ovisacs, each 
containing several more eggs, enlarged on the same scale and represented in fig. 3e, have 
been laid by the large female drawn in fig. 3d. The eggs are comparatively large. 
LARVA. A free specimen (fig. 3k) is °2]1mm. in length. The cephalothorax is an 
oblong oval (the length in proportion to the breadth is as 13:8). It can be distinguished 
from the other species by the decoration of its front: there are no naked lists, but from one 
antennula to the other, with only a very short central interruption, runs a transverse curve 
of fine processes; on the sub-median part of the front the anterior ends of the processes 
are decidedly a little removed from the frontal margin. whereas in the more lateral part, 
they almost reach the margin, and this is due to a break in the transverse curve just in 
the middle between the median line and each antennula, so that the sub-median processes 
recede a little. The olfactory seta of the antennule is extremely long, nearly as long as 
the cephalothorax and, when turned backward, reaching the middle of the abdomen. Antenne 
