PROTOZOA. O 



Subclass 1. Telosporidia. 



Speculation phase of the life-cycle is distinct 

 from and follows the trophic phase. Sporozo- 

 ites are gregarinulse. 



Order 1. Gregarinoidea. 



The young stages are intracellular parasites, 

 while the adults are free and motile in cavities 

 of the body of the host. Sporulation occurs 

 within a cyst during the free period of the life- 

 cycle. (Gregarina.) 



Order 2. Coccidia. 



Without a free and motile adult stage. Re- 

 production by both schizogony and sporogony, 

 the latter occurring within a cyst during the 

 intracellular period of the life-cycle. (Eimeria.) 



Order 3. Hsemosporidia. 



Living chiefly in the blood-corpuscles of verte- 

 brates. In many forms the entire sexual 

 period of the life-cycle takes place in an 

 intermediate host, as the mosquito. (Plas- 

 modium.) 

 Subclass 2. Neosporidia. 



Sporulation takes place during the "trophic" 

 phase of the life-cycle. Sporozoites are amce- 

 bulse. 



Order 1. Myxosporidia. 



Typically tissue parasites. Principal trophic 

 phase is a multinucleate plasmodium. Spores 

 usually with two polar capsules. (Myxidium.) 



Order 2. Actinomyxidia. 



Spore-forming phase is a binucleate amcebula. 

 Spore large with three polar capsules. (Sphse- 

 ractinomyxon.) 



Order 3. Microsporidia. 



Amceboid trophozoites. Spores very minute 

 and with but one polar capsule. (Nosema.) 



Order 4. Sarcosporidia. 



The initial stage of the life-cycle occurs in the 

 muscle cells of vertebrates. Spores with a 

 single polar capsule. (Sarcocystis.) 



Order 5. Haplosporidia. 



Spores are simple uninucleate cells without 

 polar capsules. (Haplosporidium.) 



