The gastrovascular cavity in Metridium is a single organ that functions for both digestion and circulation. It has a single opening that serves as both the mouth and anus. The cavity is divided into chambers by mesenteries radiating from the body wall, including 6 pairs of primary and 2 pairs of complete mesenteries on each side of the siphonoglyphs. The spaces between the mesenteries are called interseptal or inter-mesenteric chambers.

1. Gastro-vascular Cavity In Metridium
The gastrovascular cavity is the primary organ of digestion and circulation
Single opening to outside is both
anus and mouth
Waste and undigested materials
GVS itself divided into no of
chamber by mesenteries radiating
from body wall.

3. Two types complete and incomplete or
primary mesentery extend in body wall to
wall of pharynx.
 6 pairs of primary and 2 pairs of
complete mesentery on side of
siphonoglyphs are called directed pairs.
 The space between mesentery is called
intersepatal or inter- mesenteric
chambers.