114 bulletin: museum of comparative zoology. 



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 3^ times longer than broad (Fig. le 

 and 1/). 



Head. It is completely fused with the first thoracic segment. The eyes are 

 very small, light grayish, and scarcely ^-isible 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 antennulse and the antennse (Fig. 1 g); the margin 

 is rather slightly curved. The antennnlae tolerably short, 3-jointed; the basal 

 joint longer and very much thicker than the second ; the third joint very 

 slender and rather short. The antennae 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, -n-ith their lateral outline 

 feebly rounded and the incisions between them short. Each segment with a 

 median, rather high, basally very broad and distaUy rounded cone on the ventral 

 side (Fig. 1/) ; 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 ^\'ith the thorax and 

 consequently not drawn — are easily seen. 



Abdo^meyi. 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 Avith 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 Httle 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. 



