KEY TO CLASSES AND ORDERS OF ANIMALS 7 



3(2) Body naked or with shell, with stiff raylike pseudo- 

 podia which contain an axial filament. (Pratt, 21; 

 W. and W., 234.) Order Heliozoa 



4(1) Central capsule present, marine animals; form rela- 

 tively permanent; pseudopodia ray like. (Pratt, 24.) 



Order Radiolaria 



Class SPOROZOA 



1(2) Spore formation occurring only at the end of the vegeta- 

 tive period. Reproduction takes place by budding or 

 splitting from the outer surface of the body. 



Subclass Telosporidia, p. 7 



2(1) Spore formation occurring throughout the vegetative 

 period. Reproduction by a process of internal gem- 

 mation. Subclass Neosporidia, p. 7 



Subclass TELOSPORIDIA 



1(2, 3) Body never ameboid, usually elongated. Young 

 stages intracellular (apparently two celled). Full- 

 grown forms free in open spaces of their hosts. Para- 

 sites of invertebrates. (Minchin, 326; Calkins, 57; 

 Pratt, 42.) Order Gregarina 



2(1, 3) Spherical or ovoid; intracellular; never free in cavities 

 of hosts; parasitic in solid tissues. (Minchin, 341; 

 Calkins, 62; Pratt, 46.) Order Coccidida 



3(1, 2) Full-grown form wormlike or ameboid in blood 

 corpuscles or plasma of vertebrates. (Minchin, 356; 

 Calkins, 65; Pratt, 46.) Order Haemosporidia 



Subclass NEOSPORIDIA 



1(2, 3, 4) Ameboid in cavities of host, or encysted in tissues. 

 Multinucleate. Mostly in fishes and arthropods. 

 Spores with two or four polar capsules containing more 

 or less easily seen threads. (Minchin, 399; Calkins, 

 66; Pratt, 48.) Order Myxosporidia 



