470 Wisconsin Academy of Sciences, Arts, and Letters. 
spines. The fifth segment of the female has a projecting tooth 
at the middle of the dorsal surface. 
The first abdominal segment of the female exceeds the rest 
of the abdomen in length. It is much dilated in front. The 
lateral dilatations are rather slight, at the proximal fourth of 
the length, and armed with minute spines. The second and 
third segments are about equal in length, and each is somewhat 
shorter than the furca. The furcal rami are longer than broad 
and ciliate on the inner margin. 
The antennae are 25-segmented and reach to the end of the 
furca. The right antenna of the male is much swollen anterior 
to the geniculating joint; the antepenultimate segment bears a 
stout hook which is about one-half the length of the penultimate 
segment. 
The spines on the posterior surface of the first basal seg¬ 
ments of the female fifth feet are prominent. The lateral hairs 
of the second basal segments are slender. The length of the 
first segment of the exopodite is more than twice its width. 
The second segment is prolonged into a hook of slight curva¬ 
ture, and is denticulate on the inner margin. The third seg¬ 
ment is distinct and armed with two spines. The endopodite 
is one-segmented, about one-half the length of the first segment 
of the exopodite, and setose at the tip. 
The first basal segments of the fifth feet of the male are 
each armed with a prominent slender spine as in the case of 
the female fifth feet. The second basal segment of the right 
foot is as broad as long. It has a tooth-like process at the 
middle of its inner margin and a small hyaline process on the 
posterior surface near the distal end of the segment. The lat¬ 
eral hair is near the distal end. The first segment of the ex¬ 
opodite is short, its length being a little more than one-half its 
breadth. It is produced at the outer distal angle, and bears a 
small fold on the posterior surface near the distal end. The 
second segment is stout, its length being to its breadth in the 
proportion of three to two. The lateral spine is situated to¬ 
wards the distal end, is straight, and equals in length the two 
segments of the exopodite. The terminal hook is slender, and so 
