cephalopod coelom visceropericardial coelom The largest coelom in cephalopods except in the Octopoda where it is greatly reduced. Geneally it encloses the gonad, and partially the stomach, caecum and ventricle among other structures. Eggs and sperm are released into the coelom and picked up by the gonoducts. The visceropercardial coelom also communicates with the other cephalopod coelom, the nephridial coelom, and the mantle cavity via a pair of ducts that open at the base of the nephridial papillae.