1042 Wisconsin Academy of Sciences, Arts, and Letters. 
The third foot (PL LXX, figs. 4, 5) has a large exopodite, 
a thin, somewhat quadrate plate. It bears five large, plumose 
setae, three on the end and two on the side, of which one 
bends up and curves around the branchial sac. The endopo- 
dite has three lobes. The outer one has two setae, of which 
the outer is rather to be called a claw, on its end, and one on 
the posterior face. The middle lobe has one seta on its edge 
and two or perhaps three on its face; while the inner lobe is 
much broader and has eight setae, four on the edge and four 
on the face. All of those on the face form a row of eight 
setae, extending across the endopodite, nearly evenly spaced 
and with little reference to the lobes in their arrangement. 
The maxillary process is well developed. It is bent over so 
as to form a sort of scoop-shaped structure, concave forward 
and with finger- or hornlike projections. There are four 
long, 2-jointed setae on it as in the second foot; there is also 
a small, recurved, hairy seta on the face of the maxillary 
process, evidently the same as that which is so large in the 
fourth foot. The branchial sac is larger than in the second 
foot and of much the same shape. 
The fourth foot (PI. LXX, figs. 6, 7) is essentially like the 
third but smaller and with fewer setae. The exopodite has 
the same structure and the same number of setae; but these 
are much shorter than on the third foot, except that which 
bends around the branchial sac. The outer lobe of the en¬ 
dopodite carries a clawdike seta; the middle lobe has one; 
and the outer lobe two setae. These are 2-jointed, with a 
thick base and a short second joint, carrying long, close-set 
hairs; the whole structure having the appearance of a brush. 
On the posterior face of the endopodite are five setae; one of 
which apparently belongs to the outer and one to the middle 
lobe and three to the inner lobe. The maxillary process is 
much reduced. Its main part is a large, densely plumose, 
geniculate seta. The branchial sac is large and oval. 
The fifth foot (PI. LXXI, fig. 1) is very different from the 
preceding; next to the first, it is the largest of the series. As I 
understand the appendage, there is a large exopodite, bearing 
one long recurved seta which bends around the branchial sac. 
