ZOOMASTIGINA, RHIZOMASTIGINA 



237 



M. aspera S. (Fig. 107, c). Subspherical or oval; during locomo- 

 tion elongate and narrowed anteriorly, while posterior end 

 rounded or lobed; numerous pseudopods slender, straight; nu- 

 cleus near flagellate end; 2 contractile vacuoles; 150-200^1 by 

 about 50/x; in ooze of pond. 



M. longifilum Stokes (Fig. 107, d). Elongate, transparent flagel- 

 lum twice body length; pseudopods few, short; contractile vacu- 

 ole anterior; body 28^^ long when extended, contracted about 10/x 

 stagnant water. 



M. setosa (Goldschmidt) (Fig. 107, e). Up to 140/x long. 



Fig. 108. a, Mastigamoeba hylae, X690 (Becker); b, Adinomonas 

 mirabilis, X1140 (Griessmann); c, Dimoryha mutans, X940 (Bloch- 

 mann); d, Pteridomonas pulex, X540 (Penard); e, Histomonas melea- 

 gris, X940 (Tyzzer); f, Rhizomastix gracilis, X1340 (Mackinnon). 



M. hylae (Frenzel) (Fig. 108, a). In hind gut of frogs and tad- 

 poles; 80-100/x by 20ju; flagellum about IOjjl long. 



Genus Mastigella Frenzl. Flagellum apparently not connected 

 with nucleus; pseudopods numerous, digitate; body form changes 

 actively and continuously; contractile vacuole. 



M. vitrea Goldschmidt (Fig. 107,/). I50fx long; sexual reproduc- 

 tion (Goldschmidt). 



Genus Actinomonas Kent. Generally spheroidal, with a single 



