78 



PROTOZOOLOGY 



Fig. 30. a-c, Mtiller's vesicles in Loxodes (a, b) and in Remanella 

 (c) (a, Penard; b, c, Kahl); d, concrement vacuole of Blepharoprosth- 

 ium (Dogiel). cf, centripetal fibril; eg, concrement grains; cp, cap; fw, 

 fibrils of wall; p, pellicle; vp, vacuolar pore; w, wall. 



tozoa which take in whole or parts of other organisms as food. The 

 food vacuole is a space in the cytoplasm, containing the fluid 

 medium which surrounds the protozoans and in which are sus- 

 pended the food matter, such as various Protophyta, other Pro- 

 tozoa or small Metazoa. In the Sarcodina, the Mastigophora and 

 the Suctoria, which do not possess a cytostome, the food vacuoles 

 assume the shape of the food particles and, when these particles 

 are large, it is difficult to make out the thin film which surrounds 

 them. When minute food particles are taken through a cyto- 

 stome, as is the case with the majority of euciliates, the food vacu- 

 oles are usually spherical and of approximately the same size 

 within a single protozoan. In the saprozoic Protozoa, which ab- 

 sorb fluid substances through the body surface, food vacuoles 

 containing solid food, of course, do not occur. 



The chromatophore and associated organellae 



In the Phytomastigina and certain other forms which are 

 green-colored, one to many chromatophores (Fig. 31) or chloro- 

 plasts containing chlorophyll occur in the cytosome. The chroma- 



I 



