Marshall—Ten Species of Arrenuri. 
157 
dorsal lino runs over on the appendage. The first and fourth 
pairs of ventral plates are the largest. The first are closely 
united, all are fully outlined, and no peculiar pores or mark¬ 
ings were found,—in all of these points differing from Pier- 
sig’s figure (Dent. Hvdrach., fig. 112, a). The genital areas 
are large, pear-shaped, and extend straight outward to form 
rolls at the base of the appendage. 
The appendage is constricted a little at the base, broadens 
out and becomes slightly higher in the middle, and then nar¬ 
rows conspicuously near the end where it is again slightly 
wider. The end bows out a little and has a small depression 
in the middle line where lies a little low rounded hump. Small 
elevations which show as light scallops in dorsal or ventral view 
form, when viewed laterally, a conspicuous comer projection 
on each side of the appendage (Eg. 8, a and c, H, 3 E). Just 
in front of the last constriction of the appendage is a pair of 
small round-topped humps close together in the middle line 
(H 2 ). 
The palpi are short and stout. There are a. few hairs, most 
of them] on the second joint, with three bristles in a bunch at 
the anterior end on the convex side, while another is found on 
the inner side. The fourth segment has a broad curved bristle 
on the anterior edge. 
The first pair of legs have a few short coarse hairs and thorns 
on every segment but the last, which is provided with a row 
of finer short hairs. The second pair of legs resemble the first, 
but have a few fine hairs on the fourth and fifth segments as well 
as some short ones on the sixth. The third pair of legs bear 
longer hairs and bristles, the former confined mostly to the third 
and fourth segments. On the last pair of legs all segments 
have several bristles and thorns. The third, fourth and fifth 
joints have many fine hairs. The process on the fourth joint 
is moderately stout and bears four short, curved, stiff hairs. 
The length of this pair of legs is 1.15 nun. All of the joints 
except the last are stout. 
