Coelenterates

Coelenterates have a comparatively simple physiology. They are basically a sac of jelly which contains their internal organs. The sac has an opening their mouth, this is surrounded by tentacles. The tentacles have stinging structures called nematocysts, which are used to stun or paralyse their prey. After stinging, the tentacles pull the prey into the mouth. Each individual is known as a polyp. Coelenterates that are found on Cornish shores include the sea anemones, true jellyfish and the hydroids.


SEA ANEMONES	TRUE JELLYFISH	HYDROIDS


Sea anemones are the most eye-catching creatures to be found in rock pools.	Jellyfish are sea-going creatures, but every year hundreds are washed up on the shore.	Hydroids are colonies of polyps. Each polyp is similar to a small sea anemone.

Coelentrates