Chapter Xine 



BRYOZOA 



(Moss Animals or Corallines) 



These are colonial animals, many of which 

 resemble Hydroids. They are, however, more com- 

 plex in structure and belong to a higher branch of 

 the animal kingdom. 



There are two main types of Bryozoa, the up- 

 right type and the encrusting type. The former 

 more closely resemble hydroids and sea-weeds. The 

 common Bryozoa, Bugula, is frequently preserved as 

 a hvdroid or as an alga. The group is sometimes 

 called Polyzoa. 



Contrasted to the hydroids, each individual 

 (zooecium) of the Bryozoan colony is a complete 

 organism and there is no "division of labor." The 

 tentacles on the bryozoan are ciliated (covered with 

 hairs) whereas thoce of the hvdroid are smooth. The 

 complete digestive system of the Bryozoa also helps 

 distinguish it from the hvdroid. 



The encrusting bryozoa are sometimes called 

 Sea Mats. Many form delicate lace-like coverings 

 t<» shells, stones, etc, Other species are more massive 

 and resemble corals — hence their popular name, 

 ( Joralline. 



A pocket lens or microscope is needed to dis- 

 tinguish the different species. 



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