4 Univeysitij of ('alifdniia Publications in Zooloyij [Vol. 20 



intestine with a small drop of normal salt solution before making the 

 smear. The material thus treated may be spi-ead with less mechanical 

 injury and the albumen prevents the great loss of organisms that would 

 otherwise occur when it is placed in the fixing fluid. The addition of 

 albumen, however, necessitates quick work in making the prepara- 

 tions, to prevent the death of the organisms through its action rather 

 than that of the fixing fluids. 



OCCURRENCE 



These flagellates are more restricted in their occurrence in the 

 intestine of the host than are the other forms which are present with 

 it. They are seldom found far away from the mucus of the epithe- 

 iium, usually attaching themselves to it (pi. 1, fig. 9) by means of 

 the holdfast-like anterior end of the body. They may be seen com- 

 pletely filling the folds of the wall of the intestine with the posterior 

 portion projecting iiito the lumen of the canal. 



Near the anterior part of the posterior region of the intestine, 

 immediately behind the origin of the malpighian tubules, a slight 

 enlargement of the intestine may be noted, with one side marked by 

 two lines of constriction passing backward for a short distance. This 

 forms a rounded chamber marked off from the main portion of the 

 canal. In cross-sections this may be found completely filled with 

 StrehloniaMix, a dense coating of the flagellates attached to the wall 

 and others filling the remainder of the cavity. Plate 2, figure 8 shows 

 a small portion of the wall in this region with a few only of the at- 

 tached flagellates. 



These flagellates occur much less frequently in other parts of the 

 posterior and mid-regions of the intestine, but when present are alwaj's 

 restricted to the peripheral zone with the larger flagellates occupying 

 the remainder of the lumen. They have been found in nearly seventy 

 per cent of the hosts examined. 



JIORPHOLOGY 



Htrchlomastix is profoundly a linear organism. Elongation dom- 

 inates all of its organelles in adaptation to its crowded grouping in 

 its parasitic habitat. This elongation affects not only the body as a 

 whole but also the nucleus, rhizoplast, and flagella, and pervades not 

 only the normal vegetative trophozoite, but also the gigantic over- 



