226 



PRACTICAL ZOOLOGY 



often found in fresh water, and in the sea the snail-like shells of 

 Globigerina and many others occur in great abundance (Fig. 

 135, D). Two common flagellated Protozoa of the Euglena type 



FIG. 136. Parasitic protozoa. 



A, a cyst of monocystis full of spores ; B, a cyst of plasmodium with spores 

 escaping; C, the germs which cause syphilis; D, entameba which causes 

 dysentery ; E, the germ which causes sleeping sickness. (After various authors.) 



are Mastigameba (Fig. 135, E) and Chilomonas. Mastigameba 

 looks something like an Ameba with a flagellum at one end. 

 Chilomonas possesses two flagella. 



