236 PROTOZOOLOGY 



Genus Khawkinea Jahn and McKibben. Similar to Genus Eu- 

 glena, but without chromatophores and thus permanently colorless; 

 fresh water. 



K. halli J. and Mc. 40-45^ (30-65m) by 12-14^; fusiform; pellicle 

 spirally striated; plastic; flagellum slightly longer than body; 

 stigma 2-3/i in diameter, yellow-orange to reddish-orange, composed 

 of many granules; numerous (25-100) paramylon bodies elliptical 

 or polyhedral; cysts 20-30/i in diameter; putrid leaf infusion; 

 saprozoic. 



K. ocellata (Khawkine). Similar to above; flagellum 1.5-2 times 

 body length; fresh water. 



Genus Phacus Nitzsch. Highly flattened; asymmetrical; body- 

 form constant; pellicle often with prominent longitudinal or oblique 

 striae; a flagellum and a stigma; nucleus posterior; a short "cyto- 

 pharynx"; green chromatophores rounded discoid; with or without 

 paramylon bodies around a pja-enoid; in fresh water. Numerous 

 species. Allegre and Jahn (1943) surveyed species of this genus in 

 Iowa. 



P. pleuronectes (Miiller) (Fig. 102, a). 45-lOOju by 30-70/i; short 

 posterior prolongation slightly curved; a prominent fold on convex 

 side, extending to middle of body; longitudinally striated; one or 

 more circular paramylon bodies; colorless forms sometimes appear; 

 flagellum as long as body. 



P. longicaudus (Ehrenberg) (Fig, 102, 6). 120-170^ by 45-70/x; 

 usually twisted with a long caudal prolongation; stigma prom- 

 inent; discoidal paramylon body central; pellicle longitudinally 

 striated. 



P. pyrum (E.) (Fig. 102, c). About 30-50iu long; pyriform, with a 

 short caudal prolongation; pellicle obliquely striated. 



P. triqueter (E.) (Fig. 102, d). 50-55m by 30-35^; ovate; with a 

 longitudinal ridge; posterior end acuminate; oblique striation dis- 

 tinct; 1-2 paramylon bodies, 



P. anacoelus Stokes (Fig. 102, e). About 42^ long; oval or round; 

 with flagellum as long as body. 



P. acuminata S. (Fig. 102, /). About 30-40/z by 20-30/x; nearly 

 circular in outline; longitudinally striated; fold long; flagellum as 

 long as bod}^; 2 small paramylon bodies. 



Genus Crumenula Dujardin {Lepocinclis Perty). Body more or 

 less ovo-cylindrical; rigid with spirally striated pellicle; often with a 

 short posterior spinous projection; stigma sometimes present; nu- 

 merous discoidal chromatophores marginal; paramylon bodies usu- 

 ally large and ring-shaped, laterally disposed; without pyrenoids; 

 fresh water. Several species. 



