ZOOMASTIGINA, RHIZOMASTIGINA 



265 



M. setosa (Goldschmidt) (Fig. 113, e). Up to 140^ long. 



M. hylae (Frenzel) (Fig. 114, a). In hind gut of frogs and tadpoles; 

 80-100m by 20)u; flagellum about 10m long. 



Genus Mastigella Frenzel. Flagellum apparently not connected 

 with nucleus; pseudopods numerous, digitate; body form changes 

 actively and continuously; contractile vacuole. 



M. vitrea Goldschmidt (Fig. 113,/). 150/x long; sexual reproduction 

 (Goldschmidt). 



Fig. 114. a, Mastigamoeha hylae, X690 (Becker); b, Adinomonas 

 mirabilis, X1140 (Griessmann) ; c. Dimorpha mutans, X940 (Blochmann); 

 d, Pteridomonas pulex, X540 (Penard); e, Histomonas meleagridis, X940 

 (Tyzzer); f, Rhizomastix gracilis, X1340 (Mackinnon). 



Genus Actinomonas Kent. Generally spheroidal, with a single 

 flagellum and radiating pseudopods; ordinarily attached to foreign 

 object with a cytoplasmic process, but swims freely by withdrawing 

 it; nucleus central; several contractile vacuoles; ho lo zoic. 



A. mirabilis K. (Fig. 114, 6). Numerous simple filopodia; about 

 lOju in diameter; flagellum 20/i long; fresh water. 



Geuus Dimorpha Gruber. Ovoid or subspherical ; with 2 flagella 

 and radiating axopodia, all arising from an eccentric centriole; nu- 

 cleus eccentric; pseudopods sometimes withdrawn; fresh water. 



D. mutans G. (Fig. 114, c). 15-20^ in diameter; flagella about 20- 

 30m long. 



Genus Pteridomonas Penard. Small, heart-shaped; usually at- 

 tached with a long cytoplasmic process; from opposite pole there 



