Genitalia of (Ancistrocephalus) polypteri. 259 
linear position, and was grape-like. Near the middle of the 
ovary I was able to identify a more darkly stained globular 
shell-gland. ‘The ovary is medial, posterior, and ventral in 
each segment (fig. 4). 
In a few segments [ was able to trace a thick duct, which 
I believe to be the vagina, From the stained specimens 
nothing more was recognizable. From a few transverse 
sections indications of a coiled condition were visible (fig. 3). 
The genital opening was ventral and median. The pore 
was surrounded by muscles, and the deeply stained area under 
it suggested a cirrus. 
I found no separate opening for the vagina, so I concluded 
it opened together with the cirrus into a genital atrium 
(fig. 4). 
Uterus.—The uterus appeared to be sac-like and distended. 
In every segment it was located more dorsally, causing a 
bulging ” of the dorsal surface. 
It was situated, now on the right of the genital pore, with 
its convexity to the right, and now to the left, with the con- 
vexity to the left. This condition alternated irregularly. In 
nearly all my stained segments and transverse segments the 
uterus was distended and filled with eggs. In some of the 
stained segments the beginnings or “ aulagen”’ of the uterus 
showed up as stained curves either to the right or to the left 
of the genital pore. There was a separate uterine pore in 
every ripe segment. This aperture was situated at the ante- 
rior portion on the ventral surface, and displaced slightly to 
the left or to the right of the genital pore and the median 
line—a condition depending upon the position of the uterus 
(fig. 5). 
Vitelline Glands. 
These were confined to the lateral fields of the segments, 
and more or less in parallel rows. ‘Transverse sections 
showed them to be situated near the dorsal and ventral 
surfaces respectively (fig. 4). 
Lateral canals were visible as two longitudinal stained lines 
in the immature segments. In the sections they were not 
always visible, as they were small. In some they appeared 
laterally as two narrow ducts. I was unable to trace any 
transverse canals either in the stained segments or in the few 
sections, 
Chalk bodies were visible, especially in the sections, as 
numerous refringent granules in the body-wall. 
