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A phylum of small sessile aquatic animals living as small tufted colonies. Some appear like hydroids or corals, but their internal structure is more advanced. Most bryozoans are matlike, forming thin encrustations on rocks, shells, or kelp. (Storer & Stebbins, General Zoology, 6th ed, p443)

[Gr.] (Zool.) General name for plant-like animals; as sponges (Protozoa), corals and sea-anemones (Coelenterata), and sea-mats (Polyzoa).