APPENDIX 797 



Class Flagellata. Protozoans that swim by flagella. The group probably 



most nearly related to one-celled plants. Euglenas. 



Class Rhizopoda. Protozoans that move by pseudopodia. Amebas, 



Class Sporozoa. Parasitic protozoans. Malarial parasites. 



Class Ciliata. Protozoans that move by means of cilia. Paramecia. 

 Phylum Porifera. The sponges, the simplest of the many-celled animals, in 

 many ways resembling colonies of protozoans. Fresh-water and marine 

 forms. 



Class Calcarea. With limy skeletons. Scypha (formerly called Sycon). 



Class Hexactinellida. With 6-rayed silicious spicules. Glass sponge. 



Class Demispongiae. Skeletons of elastic spongin and with silicious spic- 

 ules. Bath sponge. 

 Phylum Coelenterata. 



Class Hydrozoa. Hydralike animals, either single or colonial. Nearly all 



marine. Hydra. 



Class Scyphozoa. Jellyfishes. Aurelia. Marine. 



Class Anthozoa. Corals and sea anemones. Marine. 

 Phylum Ctenophora. Comb jellies or sea gooseberries. Marine, 

 Phylum Platyhelminthes. Flatworms. 



Class Turbellaria. Nonparasitic flatworms. Planarians. 



Class Trematoda. Many are internal parasites. Flukes. 



Class Cestoda. Tapeworms. Parasites. 

 Phylum Nemertinea. Ribbon worms. Free-living. Most of them marine. 

 Phylum Nematomorpha. Horsehair worms. Aquatic and parasitic. 

 Phylum Acanthocephala. Spiny-headed worms. Parasites. 

 Phylum Phoronida. Marine tube dwellers. 

 Phylum Gastrotricha. Microscopic. In fresh and salt waters. 

 Phylum Chaetognatha. Glassworms, arrow worms. Marine. 

 Phylum Brachiopoda. Lamp shells, about 225 living species from the great 



numbers that once existed. Marine. 

 Phylum Rotifera. Rotifers, wheel animalcules. Abound in fresh water. 

 Phylum Bryozoa. Bryozoans, moss animals. Most of them marine. 

 Phylum Nematoda. Roundworms. In soil, water, roots of plants, parasitic in 



animals. Trichina, hookworm. 

 Phylum Annelida. Segmented worms. Soil, and fresh and salt waters. 



Class Polychaeta. Most of them marine. Clamworms, Nereis. 



Class Oligochaeta. Fresh water and land. Earthworm. 



Class Hirudinea. Fresh and salt water and land. Leeches. 

 Phylum Arthropoda. Joint-footed animals. 



Class Onychophora. Few species known. Little known tropical animals, 



intermediate between annelids and arthropods. Peripatus. 



Class Crustacea. Lobsters, crabs, crayfishes, water fleas, sowbugs. Fresh 



and salt water and land. 



Class Chilopoda. Centipedes. On land, mainly tropical. 



