CHAPTER X 



SUBCLASS 2 ZOOMASTIGINA DOFLEIN 



THE ZOOMASTIGINA laclc both chromatophorcs and par- 

 amylum bodies. The body organization varies greatly from 

 a simple to a very complex type. The majority possess a single 

 nucleus which is, as a rule, vesicular in structure. In numerous 

 forms a parabasal body is present (p. 23). Myonemes are pres- 

 ent in several parasitic forms. Nutrition is holozoic, saprozoic, 

 or parasitic. Asexual reproduction is by longitudinal fission; 

 sexual reproduction is unknown. Encystment occurs widely. 

 The Zoomastigina are free-living or parasitic in various animals. 

 According to Calkins, they are divided into four orders: 



With pseudopodia besides flagella Order 1 Pantostomatida 



Without pseudopodia, but with flagella 



With one or two flagella Order 2 Protomonadida 



With two to eight flagella Order 3 Polymastigida 



With more than eight flagella Order 4 Hypermastigida 



ORDER 1 PANTOSTOMATIDA SENN 



The group contains those Zoomastigina which possess both 

 pseudopodia and flagella. Flagella vary in number from one 

 to several. Pseudopodia vary also greatly in form and in 

 number. 



The order is subdivided into two families as follows: 



With numerous flagella Family 1 Holomastigidae 



With one to three, rarely four, flagella Family 2 Rhizomastigidae 



Family 1 Holomastigidae Senn 



Genus Multicilia Cienkowski. Body spheroidal, but amoe- 

 boid. Flagella numerous, being 40 to 50 in number, long and 

 evenly distributed. One or more nuclei. Holozoic. Food is ob- 

 tained by means of pseudopodia. Contractile vacuoles are nu- 

 merous. Multiplication by fission. Diameter of body less than 

 50 microns. Fresh or salt water. 



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