4 THE PROTEUS ANIMALCULE 



(ii) The food vacuoles, spaces containing digestive fluid and ingested 

 food material, e.g., diatoms, algae, etc. Grains of sand, fat 

 globules, green vegetable organisms and other foreign bodies 

 are also frequently present in the endoplasm. 



(iii) The contractile vacuole, a space filled with, a watery fluid. 

 Evidently it functions as a drain for the finer wastes of the 

 protoplasm. As it swells it is moved to the surface, and there 

 contracts and discharges. The vacuole is formed anew, 

 usually about the same position, when the effete liquid again 

 gathers into a droplet. 



Make drawings of Amoeba at regular intervals, noting the direction of the 

 flow of the granules. The nucleus may be rendered more distinct by the 

 addition of a drop of acetic acid. 



