BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
114 
with two subequal rami, the basal part of which is thicker, somewhat fleshy, 
the distal part more lamellar; some of the rami are oblong-triangular and dis- 
tally almost produced, others are distally broader and rounded ; almost the 
whole, or at least the major basal part of the ventral surface of all rami is fur- 
nished with conspicuous rounded knots, some of which plainly show that this 
structure is a rudimentary ramification ; the pleopods decrease somewhat in 
size from before backward. Each uropod (Fig. 1) is an oblong, glabrous 
lamella, which is as large as, or a little larger than, a ramus of the first 
pleopod. 
Size, From the front to the apex of the longest uropod the specimen is 
13 mm., and to the end of the last abdominal segment 11.2 mm. ; it is 6.6 mm. 
broad. 
b. Male. 
The body is very elongate, about 34 times longer than broad (Fig. le 
and 1f). 
Head. It is completely fused with the first thoracic segment. The eyes are 
very small, light grayish, and scarcely visible when the animal is seen from 
above. The frontal part bends much downward and forms a high border, which 
covers the basal part of the antennul and the antenne (Fig. 19); the margin 
is rather slightly curved, The antennule tolerably short, 3-jointed; the basal 
joint longer and very much thicker than the second ; the third joint very 
slender and rather short. The antenne rather long, 8-jointed; the first joint 
a little longer and about twice as broad as the second, which is about as long 
as, and much thicker than, the third and especially the fourth; the four distal 
joints exceedingly small. The mouth conical and protruding, but it was 
utterly impossible to study its elements with any certainty without a 
dissection. 
Thorax. The segments, when seen from above, with their lateral outline 
feebly rounded and the incisions between them short. Each segment with a 
median, rather high, basally very broad and distally rounded cone on the ventral 
side (Fig. 1f) ; this cone is smaller on the two first segments than on the others. 
A leg of the first pair is shown in Plate III. Figure 5, and the corresponding 
leg of the fifth pair in Figure 5a; the general shape and the armature of the 
fifth and the sixth joint — the first joint as usual fused with the thorax and 
consequently not drawn —are easily seen. 
Abdomen. It occupies one third of the total length, and decreases posteriorly 
very little in breadth. The six segments are all well separated from each 
other. The five anterior segments with the lateral part almost triangular, 
when seen from above; each with a ventral cone as those in the thoracic seg- 
ments, and, besides, each pleopod is developed as a protuberance of considerable 
size and directed obliquely inward and a little backward. The sixth segment 
relatively broad, on each side with a large, narrow conical, obtuse process, 
probably the uropod, originating from the side and directed somewhat out- 
ward and much backward ; the posterior margin of the segment is angular. 
Size. It is 4.1 mm. long to the apex of the uropods. 
