THE PEOTEITS ANIMALCULE 



MOEPHOLOGT 



a. Size. — Is Amceba visible to the unaided eye ? Com- 

 pare several as regards size. Make a camera 

 drawing of an average specimen and find its 

 exact size, using the scale prepared for the mi-' 

 croscope. 



i. Shape. — "What is the shape? What determines it? 

 Is it constant ? "Why ? Note the projections, or 

 pseudopodia, of the body which are thrust out 

 at intervals. How many may a single animal 

 have ? How few ? What is the shape of a 

 pseudopodium ? Is this shape invariable ? Do 

 the pseudopodia ever branch ? Do different speci- 

 mens vary in the number and size of their pseudo- 

 podia ? What significance in the common name 

 of the animal ? Make six sketches of the outline 

 of the body at intervals of two minutes each. 



c. Structure. — Distinguish the following parts : 



1. The ectosarc (outer, clear layer of protoplasm). 



— How much of the body does it form propor- 

 tionately ? Is it visible over the entire body ? 

 Where is it most plainly seen? Is there any 

 skin or membrane outside this layer ? 



2. The endosarc (inner, granular mass of proto- 



plasm). — How much of the body does it form ? 

 Is it distinctly separated from the ectosarc? 

 Compare with the latter as regards consistency. 

 Does the endosarc ever appear on the outside 

 of the body mass ? Are all the granules of the 

 same size ? What shapes and colors have they ? 

 Are they stationary ? Why ? What other things 

 besides granules are visible in the endosarc ? 



