CYTOPLASMIC INCLUSIONS 173 



fore, have a transport function, but none of the granules of either 

 Ichthyophthirius or Flabelliila give evidence of a relationship with the 

 gastriole which would permit such a function. 



The storage of lipoids is accomplished in almost identical fashion in 

 Opdina, Ichthyophthirius, and Gregarina by the formation of inter- 

 mediate lipoid bodies which are converted into neutral fats. A. proteus 

 also stores neutral fats, but in this case no visible intermediate bodies are 

 formed. This is not necessarily in conflict with the facts observed in the 

 other species, since it is very possible that the intermediate bodies of 

 fatty acid might be present but never get as large as the lower limits of 

 microscopic visibility. However, not all the visible lipoid reserves of 

 Amoeba are in the form of neutral fat; some are in the form of masked 

 lipoids in the refractive bodies, and none of the other Protozoa in this 

 group have granules which are strictly comparable with these complex 

 structures. 



Carbohydrate reserves are found in the form of paraglycogen gran- 

 ules in Ichthyophthirius and the Sporozoa, and in both cases are secreted 

 by mitochondria. In Opalina, glycoprotein is found in certain cases in the 

 segregation apparatus, but according to Kedrowsky, there are no im- 

 portant stores of carbohydrates in this species. For Amoeba likewise this 

 statement holds, the only carbohydrate being the shell between the fluid 

 and the lipoid-protein rim of the refractive bodies. No carbohydrate 

 reserves are found in Flabellula. From these cases it would appear that 

 the function of carbohydrate storage is largely accomplished by mito- 

 chondria, but it must be remembered that this is not a general rule, since 

 these reserves may be formed by independent bodies, as in the Ophryo- 

 scolecidae, or by the parabasal body, as in certain flagellates. 



The vacuolar apparatus performs at least two functions — the excretion 

 of water to maintain the proper water balance, and the excretion of 

 other materials which are probably metabolic wastes. The first function 

 may be performed without the intervention of granules, as in the encysted 

 stages of Ichthyophthirius, but the excretion of other materials is accom- 

 panied by the periodic aggregation of granules around the vacuole in 

 Amoeba and Ichthyophthirius. In the former function the granules con- 

 form to the definitions of mitochondria, and in the latter to the Golgi 

 bodies. These bodies are certainly a group having to do, in Ichthyoph- 

 thirius, only with the contractile vacuoles; but in Amoeba they are appar- 



