706 The American Naturalist. [August, 
anterior region, slender and containing the esophagus; a thicker me- 
dian region, containing the dark-brown intestine 
and the convoluted generative tube; a posterior 
slender region sharply marked off from the 
median region by a constriction, containing the 
uncolored posterior portion of the intestine and 
the posterior portion of the generative tube. The 
latter region terminates in an enlarged and gib- 
bous copulatory bursa, which is denticulate with 
about two rows of blunt teeth on its rim, and 
contains a single, club-shaped spicule. The 
anterior and median regions are smooth or with 
faint longitudinal striations; the posterior region Fic. 2, 
is transversely wrinkled 
e cesophagus is cox slender and communicates by a rounded : 
base with the intestine, which is broader than the cesophagus, abruptly 4 
truncate at its origin and continues of nearly uniform size throughout a 
the median portion of the body. The walls of the intestine in the - 
median region of the body were seen to contain polygonal, mostly hex- | 
agonal, cells (Fig. 5]. The intestine loses its dark-brown color as it 
passes from the median to the a 
posterior region of the body. 
The anal aperture is at the base : 
of the copulatory bursa [a, Fig. 
3]. The generative apparatus. 
isa single tube which extends 
from the anterior end of the 
intestine to the copulatory bursa, 
where it opens beside the papil- 
lary termination of the intes- 
tine, [vd, Fig. 3]. In the cen- Tii 
tral region of the body it is 
much PREG sin ee posterior region of the body it is nearly Pe 
straight and thick-walled, i ; oy 
mee The spicule [Figs. 2, 3, 4], is a 
fe club-shaped, somewhat spiral 
in its middle portion, about 
twice the length of the bursa 
and less than one-fifth the 
length of the posterior divi- 
sion of the body. 
The following measure- 
ments were made on the Fic, 4. 
pory i 
A S sity E E LE a T Va 
~ 
Fic. 5. 
specimen in acetic acid: 
