SEA- ANEMONES IQI 



Fourth Type of Ccelentera. — A Sea-Anemone, such as 

 Tealia eras sic or tits. Class Anthozoa 



Most sea-anemones live fixed to the rocks about low- 

 water mark. All these fixed forms have a distinct basal 

 disc, and may, like Tealia crassicornis, be half buried in 

 sand and gravel ; others, without a basal disc, are loosely 

 inserted in the sand, e.g. Edwardsia and Cerianthiis. All 

 are able to shift their positions by short stages. Some 



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Fig. 98. — External appearance of Tealia crassicornis. 



reef-anemones {Cradactis) can crawl about on their 

 tentacles. They feed on small animals — molluscs, 

 crustaceans, worms — which are caught and stung by the 

 tentacles. Many depend on minute organisms ; others 

 may be seen trying to engulf molluscs decidedly too large 

 for them. A few anemones, without pigment or with 

 little, have symbiotic Algae in their endoderm cells ; the 

 bright pigments of many others seem to help in respiration. 

 Besides the sexual reproduction (in which the young are 

 sometimes developed within the parent), some sea-anemones 

 also multiply asexually by detaching portions from near the 

 base, and fission occurs in a few forms. 



