248 HANDBOOK OF PROTOZOOLOGY 



Two or more contractile vacuoles large. Axial filaments arise 

 from a narrow zone of dense cytoplasm at the border line be- 

 tween endoplasm and ectoplasm. Body large, diameter 80 to 

 1000 microns. Among aquatic plants in freshwater ponds. 



Genus Camptonema Schaudinn. Body spheroidal. Axial 

 filaments of axopodia end in the nuclei which are about 50 in 

 number. Contractile vacuoles (?) numerous and small in size. 

 Marine. 



Camptonema nutatis Schaudinn (Fig. 98, c). About 150 

 microns in diameter. 



Genus Oxnerella Dobell. Spherical. Cytoplasm indistinctly 

 differentiated. Eccentric nucleus with a large endosome. Axial 

 filaments take their origin in the central granule. No contractile 

 vacuoles. Nuclear division is typical mitosis (Fig. 19). 



Oxnerella maritima Dobell (Fig. 19). Small, diameter 10 to 

 22 microns. Solitary, floating or creeping. Salt water. 



Suborder 2 Chlamydophora Archer 



Body is covered by a gelatinous envelope containing no 

 silicious scales. 



Genus Astrodisculus GreefT. Spherical with gelatinous en- 

 velope, free from inclusions, sometimes absent. No demarcation 

 between the two regions of the cytoplasm. Freshwater inhabi- 

 tants. Four species. 



Astrodisculus radians Greeff (Fig. 99, a). Outer surface of 

 the investment often with adherent foreign bodies and bacteria. 

 The cytoplasm is often loaded with green, yellow, or brown 

 granules. A single nucleus eccentric; a contractile vacuole. 

 Diameter of body 13 to 25 microns. In pools and ditches. 



Genus Actinolophus Schulze. Body pyriform, enveloped in 

 a gelatinous mantle. With a stalk which is apparently hollow. 

 Axopodia long and numerous. An eccentric nucleus. Marine. 



Actinolophus pedunculatus Schulze (Fig. 99, h). Diameter 

 30 microns. Stalk about 100 microns long. In marine water. 



Genus Heterophrys Archer. Body spherical, mucilaginous 

 envelope thick, with numerous radial, chitinoid spicules which 

 project beyond its periphery; nucleus single, eccentric. Axial 

 filaments of axopodia originate in a central granule. Four 

 species. 



