it look like a round worm
An earth worm demonstrate cephalization through an an enlarged ganglion that acts as a simple brain. One particular part of the earth worms nervous system, an enlarged ganglion, does act as a simple brain, and it is located in the anterior portion of the earthworm's anatomy. Hence, the earthworm exhibits cephalization.
An earth worm is plump and long. A round worm is long and slender almost like a hair.
Cephalization
Round worms are nematoda, which are, mostly, parasitic worms. A round worm is also called a Guinea worm.
In the life cycle of the round worm, a very early life stage occurring within the uterus of the female round worm.
A hydra does not have cephalization.
the Filarial round worm causes elephantiasis
In the life cycle of the round worm, the second stage of life, sometimes considered the "adolescent" stage.
Tape worm / round worm
Ascarididae
an earth worm is longer and has more sections of the body in comparisence to a roundworm.