CHILOMASTIX MESNILI 



dents (Hinshaw, 1926b) has recently described this 

 organelle as a chromatic basal rod indicates that Kofoid 

 has changed his mind regarding its homology with the 

 parabasal body of other flagellates. Both binary longitu- 

 dinal fission and multiple fission have been observed; but 

 no other stages are known in the life-cycle. 



4. CHILOMASTIX MESNILI (Fig. lOa) 



The large intestine is the habitat of this species. The 

 trophozoite (Fig. loa) is usually from S/zto 14/1 long and 

 from one-half to one-fourth the total length in breadth. 

 Three flagella extend out from the anterior end and a 

 fourth lies within the large cytostome. On either side of 

 the cytostome is a supporting fibril. There is a large 

 nucleus near the anterior end and three blepharoplasts 

 from which the flagella arise. The cyst (Fig. lob) is 

 lemon-shaped and measures from yix to 9/^ in length and 

 from 4iu to 6/x in breadth ; nucleus, cytostome, cytostomal 

 fibrils and flagellum, and blepharoplasts are visible 

 within it. Longitudinal and multiple fission of the tropho- 

 zoite have been described and also nuclear division within 

 the cyst (Hegner, 1923c; Grasse, 1926). 



5. EMBADOMONAS INTESTINALIS (Fig. Iia) 



This species lives in the large intestine of man where 

 it occurs both in the trophozoite and cyst stages. The 

 trophozoite usually measures from 5/x to 6tx in length 

 and from 3/^ to 4iu in breadth. On one side near the 

 anterior end is a very large cytostome resembling some- 

 what a sucking disc. There are two anterior flagella 

 that arise from separate blepharoplasts situated on the 



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