CHAPTER III 



INTESTINAL FLAGELLATES 



I. Generic Characteristics 



There is still some doubt as to the number of distinct 

 species of intestinal flagellates that live in man. No 

 question exists, however, regarding the generic and 

 specific rank of Giardia lamblia, Chilomastix mesnili, 

 Embadomonas intestinalis and Trie ere omonas intesti- 

 nalis. There is some doubt, however, about Enteromonas 

 hominis, and opinions differ with respect to the genera 

 and species of the trichomonads. The classification of the 

 flagellates is not in a satisfactory state, due largely to 

 their small size, the difficulty of making adequate pre- 

 parations, and the apparent inconstancy of various char- 

 acteristics. 



I. TRICHOMONAS 



Members of this genus (Figs. 7, 8, 9) possess three to 

 five anterior flagella ; an undulating membrane to which 

 an axoneme is attached, a chromatic basal rod, a cytos- 

 tome, an axostyle, a nucleus situated near the anterior 

 end, a group of blepharoplasts, and, at least in some 

 species, a parabasal body. The vaginal trichomonad, T. 

 vaginalis, Donne (1837), is the type species; it has four 

 flagella. If the number of flagella is considered of generic 

 importance, then trichomonads with 4 flagella must be 

 included in the genus Trichomonas. The genus Tritri- 



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