468 Wisconsin Academy of Sciences, Arts, and Letters. 
The first abdominal segment of the female is slender and 
about once and a half as long as the rest of the abdomen. It 
is dilated in front and laterally. The lateral expansions are 
well forward, and are terminated with lateral spines. The sec¬ 
ond segment is short, less than one-half the length of the third. 
The furcal rami are much longer than the third segment, and 
much wider at the distal than at the proximal end. They are 
setose on the inner margin. 
The antennae are 25-segmented and slightly exceed in length 
the furcal rami. The antepenultimate segment of the right an¬ 
tenna of the male bears a hook which is considerably shorter 
than one-lialf of the penultimate segment. 
The first basal segments of the female fifth feet are armed 
with small spines. The second basal segments have short lat¬ 
eral hairs. The exopodite consists of three segments. The 
third segment is very small, and is tipped with a spine. There 
is also a small spine on the distal outer angle of the second seg¬ 
ment. The second segment is prolonged into a rather blunt 
hook which is denticulate on the inner margin. The endopo- 
dite is shorter than the first segment of the exopodite, and is 
tipped with small hairs. The two terminal spines are very 
small. 
The first basal segments of the male fifth feet are aimed 
with prominent spines. The lateral hairs of the second basal 
segments of both feet are situated near the distal end of the 
segment. The length and breadth of these segments are about 
equal, and both are strongly curved on the inner margins. From 
the middle of the inner margin of the second basal segment of 
the right foot extends a small quadrangular hyaline lamella. 
The first segment of the exopodite of the right foot is short, its 
length and breadth being about equal. On its posterior sur¬ 
face are two hyaline shelf-like projections. The second segment 
is considerably longer than the combined lengths of the second 
basal segment and the first segment of the exopodite. Its outer 
margin is strongly curved. The lateral spine is large, strongly 
curved, and situated about midway of the length of the seg¬ 
ment. From near the base of the lateral spine a transverse 
