1. Metridium is a large sessile, brightly coloured, solitary, flower-like or polyp-like marine coelenterate
2. It is largest and one of the commonest, sea anemones on the Atlantic coast, New Jersey to Labrador from low water mark to approximately 90 fathoms, Pacific coast and Europe.
3. Commonly called as Sea anemone.
4. Body is short cylindrical,radially symmetrical and longer than broad.
5. Body of the animal is divided into 3 regions-Oral disk, column, pedal disk.
6. Oral disk is expanded as a flat disk, called as capitulum , which is crowned with several marginal tentacles around the mouth.
7. Column forms major part of the body and is differentiated into 2 parts: (i) upper delicate thin walled capitulum and (ii) lower thick walled scapus.
8. Capitulum and scapus are separated by a prominent fold called a shallow groove called as fossa.
9. Pedal disk: It is a broad disk attached to the substratum and is separated from the scapus by limbus.
Source:
1. Practical Zoology Invertebrates by S.S.Lal. 2. A Manual of Practical Zoology Chordates by Dr. P.S. Verma.
