510 PROTOZOOLOGY 



Genus Astrodisculus Greeff. Spherical with gelatinous envelope, 

 free from inclusions, sometimes absent; no demarcation between 2 

 regions of the cytoplasm; pseudopodia fine without granules; fresh 

 water. 



A. radians G. (Fig. 215, c). Outer surface usually with adherent 

 foreign bodies and bacteria; cytoplasm often loaded with green, 

 yellow, or brown granules; nucleus eccentric; a contractile vacuole; 

 diameter 25-30/z including envelope; in pools and ditches. 



Genus Actinolophus Schulze. Body pyriform, enveloped in a 

 gelatinous mantle; stalked; stalk apparently hollow; axopodia long, 

 numerous; nucleus eccentric; salt water. 



A. pedunculatus S. (Fig. 215, d). Diameter about 30yu; stalk about 

 100m long. 



Genus Elaeorhanis Greeff. Spherical; mucilaginous envelope with 

 sand-grains and diatoms; cytoplasm with a large oil globule; nu- 

 cleus eccentric; 1 or more contractile vacuoles; pseudopodia not 

 granulated, sometimes forked; fresh water. 



E. cincta G. (Fig. 215, e). Bluish with a large yellow oil globule; 

 without any food particles; no central granule; pseudopodia rigid, 

 but apparently without axial filaments, sometimes forked; young 

 forms colonial; solitary when mature; outer diameter 50-60/z; body 

 itself 25-30^; in lakes and pools. 



Genus Sphaerastrum Greeff. Somewhat flattened; greater part 

 of axopodia and body covered by a thick gelatinous mantle; a cen- 

 tral granule and an eccentric nucleus; fresh water. 



S. fockei G. (Fig. 215, /). Diameter about 30/x; often colonial; in 

 swamps. 



Family 5 Heterophryidae Poche 



Genus Heterophrys Archer. Spherical; mucilaginous envelope 

 thick, with numerous radial, chitinous spicules which project beyond 

 periphery; nucleus eccentric; axial filaments originate in a central 

 granule; fresh or salt water. 



H. myriopoda A. (Fig. 215, g). Nucleus eccentric; cytoplasm 

 loaded with spherical algae, living probably as symbionts; contractile 

 vacuoles indistinct; 50-80/z in diameter; in pools and marshes; and 

 also among marine algae. 



H. glabrescens Penard. Spherical; gelatinous envelope poorly de- 

 veloped; chitinous needles indistinct; pseudopodia very long; 11— 15u 

 in diameter; fresh water. 



