INFUSORIA. 7 



Class II. Infusoria (Plegepoda). 



Protozoans with a definitely-shaped body invested by a cuticle 

 Locomotion effected, and food- and oxygen-bearing currents produced by 

 vibratile membranes, flagella, or cilia. 



Order 1. Flagellata (Mastigophora). With one or more flagella, and a 

 contractile vacuole. Reception of food effected by short broad pseudo- 

 podia, or through a cell-mouth. Some possess chlorophyll, and then 

 live partly or entirely (holophytic) like green plants. Reproduction by 

 longitudinal fission or by spores. Conjugation frequent. Monas, Cerco- 

 monas, Uroglena. Bodo. Euglena. Pandorina, Volvox, Haemato- 

 COCCUS, holophytic, and first two colonial. Codosiga, with single 

 flagellum surrounded by oral collar. Ceratium, Peridinium, and 

 Noctiluca, marine forms, with shell and two flagella. 



The lower Flagellates are allied by spore-formation and presence of 

 flagella to the Schizomycetes (Bacterium ; Leptothrix; Cladothrix), the 

 higher to the Ciliata. 



