PHYLA OF LESSER SIGNIFICANCE 



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disc seems to be revolving and resembles a wheel turning. They are 

 worm-like in appearance and seem to be closely related to the flatworms 

 and roundworms, having some characteristics of both. For instance, 

 they have flame cells like planaria, but an anus like ascaris. 



Photo by Buchsbaum 

 Fig. 18.1. A sea walnut. Photo of living animal at Woods Hole, Mass. 



Phylum — Gastrotricha 



This is another small group of animals commonly found in fresh 

 water closely associated with amoeba, Paramecium, and the rotifers. 

 They do not have the revolving wheels of cilia at the anterior end, but 

 have rows of cilia down their ventral surface for locomotion. A few are 

 also found in salt water. 



Phylum — Bryozoa 



Animals in this phylum are sometimes called moss animals because 

 they resemble moss-like plants and are often mistaken for seaweed in 

 their marine form. They develop a hard case, somewhat like the coral 

 polyps, and extend themselves from this to feed, only to draw themselves 



