MAM ,PLZ ANSWER

 Jelly fish is the another word used for medusa.Both Aurelia and Rhizostoma are medusa belonging to the same class scyphozoa.

Both Aurelia and rhizostoma are different in the following way:

 

AURELIA	RHIZOSTOMA
It is commonly called as Moon jelly fish.	It is commonly called as barrel jelly fish which is the largest jelly fish.
It tentacles are small.	It has 8 long tentacles.