INVERTEBRATE ZOOLOGY. 



PROTOZOA. 



Unicellular Animals. 



CLASS 1. Sarcodina. 



No permanent locomotor organs in "adult" 

 phase of the life history; the cells moving and 

 ingesting food by temporary pseudopodia. 

 "Young" phases may be amoeboid or flagellate. 

 (Minchin, pp. 178 and 234-237.) 

 Subclass 1. Rhizopoda. 



Forms with branched, root-like pseudopodia. 

 Locomotion chiefly by creeping. 



Order 1. Amcebcea. 



Simple amoeboid forms, typically with lobose 

 pseudopodia; with or without a simple test. 

 (Amoeba, Arcella, Diffiugia.) 



Order 2. Foraminifera. 



Chiefly marine forms with reticulose pseudo- 

 podia and complex tests. (Lecythium, Globi- 

 gerina.) 

 Subclass 2. Actinopoda. 



Chiefly spherical floating forms with slender 

 unbranched radiating pseudopodia supported 

 by an internal axial filament. 



Order 1. Heliozoa. 



Fresh- water forms without a "central capsule" 

 separating ectoplasm and endoplasm. (Actin- 

 osphserium, Actinophrys, Clathrulina.) 



Order 2. Radiolaria. 



Marine forms with a central capsule. (Thalas- 

 sicolla.) 

 CLASS 2. Mastigophora. 



Locomotor organs of adult phases consist of 

 one or more vibratile lash-like appendages or 

 flagella. 

 1 1 



