130 D. H. WENRICH 



The parabasal body is a cylindrical curved rod, of a diameter 

 comparable to that of the axostyle, connected by a narrow attach- 

 ment to the blepharoplast and lying dorsal to and to the right 

 of the nucleus. Its texture is apparently different from that of 

 any other structure in the cell and its staining reaction with 

 haematoxylin is different from the other structures. While it 

 appears to be homogeneous, its texture is of a looser, more 

 spongy nature than that of the structures so far mentioned. Its 

 appearance compares well with the figures of it given by Janicki 

 ('11). It is quite variable in length, as indicated by figures 

 3, 4, 5, 6, and 16, but when it is longer it often has a constriction 

 (figs. 4, 5), or a thinner place (fig. 16), marking off two regions. 

 One wonders if the distal portion may not become detached and 

 serve some function in metabolism. 



I have never seen any indication of a central core or thread as 

 described by Cutler ('19) for the parabasal of Ditrichomonas 

 termitis. On the contrary, in an animal which was either round- 

 ing up for encystment or else had started to degenerate (fig. 6), 

 the parabasal appeared as a granular peripheral case enclosing 

 a non-staining area. 



Since Kofoid and Swezy ('15) employed mainly Schaudinn's 

 fluid which seems to dissolve out the parabasal, this elusive 

 organelle was apparently overlooked by them, and they applied 

 the term 'parabasal' to the chromatic basal rod. The homology 

 of the above-described parabasal in Trichomonas muris with the 

 similar structures figured by Janicki ('11) for Devescovina, 

 Parajoenia, Stephanonympha, and Trichomonas and by Cutler 

 ('19) for Ditrichomonas termitis seems to me to be justifiable, 

 but a homology between the chromatic basal rod and these 

 parabasals of Janicki, as claimed by Swezy ('16), would, in my 

 opinion, be open to some question. 



D. Differences due to different fixatives 



It will be profitable, I think, to consider at some length some 

 differences of appearance in the organization of Trichomonas 

 muris which are correlated with the use of different fixatives. 

 The conditions found in the series of slides from mouse no. 24 



