The reproductive organs are modified patches of the peritoneum, or lining of the perivisceral cavity.
At this stage, also, incompletely developed Cercari may be seen in the perivisceral cavity.
It had apparently the perivisceral cavity and nephridia of the schematic worm, and a circulatory system.
Its anterior end opens, in most cases by a single opening, into the perivisceral cavity in both sexes, and is usually ciliated.
There is a perivisceral cavity, and the body walls are traversed by excretory tubes.
Beside the perivisceral cavity and its fluid there is a special circulatory system.
Within the muscles is the perivisceral cavity, and in its central axis the intestine, segmented like the body-wall.
perivisceral per·i·vis·cer·al (pěr'ə-vĭs'ər-əl)
Surrounding the viscera.