How are jellyfish and hydra similar and different?

Both jellyfish and hydra belong to the type of coelenterates, but of different classes. Hydra is a class of hydroid polyps, and jellyfish is a class of scephoid jellyfish. This means that they have both similarities and differences.
Similarities:
1. Multicellular two-layer animals with 2 germ layers: ecto- and endoderm. Between them there is an interlayer – mesoglea (primordia of 3 germ layers).
2. Jellyfish and hydras are dioecious animals, there is an alternation of generations.
3. Cellular differentiation.
4. The presence of the nervous system.
5. Cavity digestion.
Differences:
1. In addition to the diffuse nervous system of the reticular type, the jellyfish also has sense organs (light-sensitive eyes), i.e. there is its complication.
2. The intestinal cavity is more complicated in jellyfish: mouth – pharynx – stomach – intestinal cavity. The hydra has no stomach.
3. The jellyfish has tentacles 10 cm long. The hydra has stinging cells.
4. Hydras are capable of forming colonies. There is no jellyfish.