482 Wisconsin Academy of Sciences , Arts, and Letters. 
segment is very short, and the third and the furca are nearly 
equal in length. The furcal rami are ciliate on both inner 
and outer margins. 
The antennae are 2 5-segmented, and in the female reach the 
lateral processes of the first abdominal segment. The ante¬ 
penultimate segment of the right male antenna has a long, re¬ 
curved, acuminate process, which reaches about to the end of 
the antenna. 
In the fifth foot of the female, the first segment of the exo- 
podite is twice as long as wide. The second segment is pro¬ 
longed into the customary hook. This segment bears a spine 
at its outer angle and is denticulate on its inner margin. The 
third segment is distinct and hears two strong spines, of which 
the inner is longer and is serrate on its margins. 
The endopodite nearly equals in length the first segment of 
the exopodite, is indistinctly two-segmented, is setose at tip, 
and bears two rather long spines. 
In the fifth feet of the male, the spines of the first basal seg¬ 
ments are rather small. The second basal segment of the 
right foot is wider than long, has a peculiar rugose expansion 
of the inner margin, and bears the lateral hair at about two- 
thirds of its length. The first segment of the exopodite is short, 
its length being less than its breadth. It is produced on the 
outer distal angle, and hears a small tubercle on the inner 
margin near the distal end. The second segment is twice as 
long as broad, convex on the outer margin, and concave on the 
inner. The lateral spine is placed near the outer distal angle 
and is serrate on the inner side. The terminal hook is about 
as long as the whole right foot exclusive of the first basal seg¬ 
ment ; it is abruptly bent at somewhat less than half its length, 
making very nearly a right angle. The inner margin is den¬ 
tate. The endopodite is slender, indistinctly two-segmented, 
and once and a half as long as the first segment of the exopo¬ 
dite. The left foot reaches nearly to one-half the length of 
the second segment of the right exopodite. The second basal 
segment is as long as wide, with the lateral hair placed near 
the distal end. The first segment of the exopodite is twice as 
