398 



Philippine Journal of Science 



m» 



life ingested by the snail which constitute a portion of the diet 

 of the parasite. 



d e 



Fig. 1. Oral and excretory apparatus of Balantidium haughwouti. 



In this portion of the parasite the meganucleus and the micro- 

 nucleus can be seen, floating and eddying about in most intimate 

 association in the rapid and constant cyclosis of the endoplasm ; 

 abundant food vacuoles ; fragments of vegetable cells or smaller 

 protozoa, partially digested; and, in some instances, contractile 

 vacuoles. In stained preparations of lean individuals, where the 

 alveolar structure does not obstruct the view, this area is 

 traversed by an intricate system of numerous minute, canal-like 

 structures (see fig. I, b), seen as clear homogenous-appearing 

 lines running through the granular substance. Whether they 

 represent true canals, lines of conduction of excretory products, 

 or are merely artifacts due to unequal shrinkage of protoplasmic 

 elements in the fixing fluid, remains to be determined. 



If the former, we should have a condition such as that obtain- 

 ing in the gregarine-like infusorian Pycnothrix monocystoides. 



