We just learned about the Velarium.
Another part of a jellyfish's body is an Amebocyte.
These are teeny tiny little animals that live in a jellyfish's body and will help eat up junk that the jellyfish doesn't want to eat.
Some of them look like tiny little crabs or clams.
(from: wikipedia - amebocyte)
Kid Facts - Blast from the past: Statocyst