POLYMASTIGINA 



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in mammals, da Fonseca (1915) originally observed only 3 flagella 

 and no cysts; 4 flagella and encysted forms were noticed in Tri- 

 cercomonas by Wenyon and O'Connor (1917); in da Fonseca's ori- 

 ginal preparations, Dobell (1935) observed 4 flagella as well as cysts 

 and concluded that Enteromonas and Tricercomonas are one and 

 the same flagellate. 



Fig. 156. a, Tetramitus rostratus, X620 (Lemmermann); b, T. pyri- 

 formis, X670 (Klebs); c. T. salinus, X1630 (Kirby); d, Collodictyon 

 triciliatum, X400 (Carter); e-j, Costia necatrix (e, f, XSOO (Weltner); 

 g-i, X1400 (Moroff); j, two individuals attached to host integument 

 X500 (Kudo)); k, Enteromonas hominis, X1730 (Wenyon and O'Con- 

 nor); 1, Copromastix prowazeki, X1070 (Aragao). 



E. hominis da F. (T. intestinalis W. and O) (Figs. 156, k; 157, ad). 

 Trophozoites 4-l(hz by 3-6ju; nucleus circular or pyriform, with a 

 large endosome, near anterior end; 4 flagella take their origins in 

 blepharoplasts located close to nucleus; cytoplasm vacuolated or 

 reticulated, contains bacteria; cysts ovoid, 6-8/x by 4-6/z; with 1, 2, 

 or 4 nuclei; commensal in the lumen of human intestine; found in 

 diarrhoeic stools. Widely distributed. 



E. caviae Lynch. Similar to the species mentioned above, but 

 slightly smaller; in the caecum of guinea-pigs (Lynch, 1922). Cytol- 

 ogy (Nie, 1950). 



