Phylum - Echinodermata

 ◆ The name echinodermata was coined by Jacob Klein in 1734.

General characters :

1.Adults with radial with 5rays symmetry.

2. Body divisible into oral and aboral surface.

3. The surface of the body is covered by calcareous ossicles or plates.

4. On the underside are 5 groove called ambulacra.

5. Digestive canal is mostly coiled tube.

6. Presence of water vascular system is the most characteristic features.

7. Circulatory or haemal or blood lacunar system is typically present.

8. nervous  system is primitive.