AMOEBA 39 



2. The inner granular mass is the endoplasm. Structure? 

 Movement? "Within the endoplasm distinguish food vacuoles, 

 which are usually dark in color and maj^ be of any shape or size, 

 and the small water vacuoles which appear grey or colorless and 

 are alwaj^s perfectly spherical in form. 



3. The blunt processes which are thrust out from time to 

 time and retracted are pseudopodia (false feet). How are they 

 formed? Do any of them branch? About how many can you 

 count at any given time? Are they confined to any particular 

 part of the body? Mention two functions which they perform. 

 Notes required. 



4. Describe in detail the method of locomotion in the 

 Amoeba, telling what part the ectoplasm and the endoplasm each 

 plays. Is there any coordination in movements? Notes required. 



5. Find an Amoeba that is moving actively. Make six 

 outline sketches of your specimen at intervals of approximately 

 twenty seconds to show the changes of form. Each drawing 

 should be at least 40 mm, in diameter. 



6. Note differences in number and in arrangement of 

 pseudopodia in an Amoeba that is floating free in the water and 

 in one that is creeping upon the surface of the slide or cover- 

 glass. 



7. Watch an Amoeba feeding and describe the process of 

 taking food. Watch and describe any changes in particles of 

 food which have been engulfed. Where does digestion take 

 place? What becomes of the food particles? Notes required. 



8. Contractile Vacuoles. Find one or more. They are 

 circular in outline and disappear from time to time. Note and 

 describe carefully the method of disappearance and reappear- 

 ance. Has the contractile vacuole any color? Any definite po- 

 sition in the body? In which body layer? Source of its con- 

 tents? Nature of its contents? What becomes of the contents 

 when a vacuole disappears? Notes required. 



