INVERTEBRATE ZOOLOGY. 



PROTOZOA, 



Unicellular Animals. 



Subphylum 1. Sarcodina. 



No permanent locomotor organs in ''adult" phase 

 of the life-history; the cells moving and ingest- 

 ing food by temporary pseudopodia. * 'Young" 

 phases may be amoeboid or flagellate. (Min- 

 chin, pp. 178 and 234-237). 

 Class 1. Actinopoda. 



Chiefly spherical floating forms with slender un- 

 branched radiating pseudopodia supported by 

 an internal axial filament. 



Subclass 1. Heliozoa. 



Fresh-water forms without a "central capsule" 

 separating ectoplasm and endoplasm. (Actino- 

 sphserium, Actinophrys, Clathrulina.) 



Subclass 2. Radiolaria. 



Marine forms with a central capsule. (Thalas- 

 sicola.) • 

 Class 2. Rhizopoda. 



Forms with branched, root-like pseudopodia. 

 Locomotion chiefly by creeping. 



Subclass 1. Proteomyxa. 



Forms with ray-like pseudopodia frequently 

 branching and with no axial filaments. (Nu- 

 clearia.) 



Subclass 2. Mycetozoa. 



Semiterrestrial forms with myxopodia and 

 Plasmodium formation. (Stemonitis.) 



Subclass 3. Foraminifera. 



Chiefly marine forms with reticulose pseudo- 

 podia and complex tests. (Lecythium, Glo- 

 bigerina.) 



