THE PROTOZOA 



Ins- 



has been said to cause pyorrhea alveolaris (Fig. 55), but Rivas 

 holds that these Amoebae are the effect of infection and thus represent 

 a secondary infection which aggravates the primary infection. 

 Class II. Sporozoa 



Subclass 1. Telosporidia ( ) 



Order 3. Haemosporidia ( ) 



Plasmodium which causes malaria. (See Fig. 50.) 

 Subclass 2. Neosporidia ( ) 



Order 2. Sarcosporidia ( ) 



Sarcocystis miescheriana. (Fig. 56.) 



Medical men often call these organisms "Rainey's tubes." 

 They are found in the muscles of pigs. 



These tubes are ovoid bodies filled with small sickle-shaped 

 unicellular organisms the sarcocystis miescheri. It sometimes is found 

 in man, causing serious disease called psorospermiasis, usually fatal. 

 Class III. Mastigophora 

 Order 1. Flagellata 

 Trypanosoma gambiense (Fig. 57) causes the disease known 



Fig. 56. 



Longitudinal section 

 through muscle of a Pig, 

 c o n t a ining Sarcocystis 

 Miescheriana ( K u h n ) . 



(After Braun.) 



Fig. 57. 



Trypanosoma gambiense, from 

 a case of sleeping sickness. 

 Different forms. (After Man- 

 son.) 



as trypanosomiasis, commonly known as sleeping sickness. 



These parasites are found in many invertebrates and verte- 

 brates. 



Life history in two stages. One "a flagellate monadine 

 ( ) phase, in which they live in the blood-stream 



of vertebrates, and in some of which they cause serious disease; the 

 other is a gregarine ( ) non-flagellate phase which 



may also be parasitic and which is met with in forms of Kala-Azar." 



Causes sleeping sickness, which is common in West Africa. 

 Those living on "wooded shores of lakes and rivers, such as fishermen 

 and canoe men are subject to it. The parasite is carried "by the bite 



