18 THE BIOLOGY OF THE CELL 



engaged in the process? "What changes are 

 noticed in the animals after conjugation ? 

 Make drawings showing the process of fission in sev- 

 eral different stages and of conjugation. 



General Questions.- — "Which is the " higher " animal, 

 Paramecium or Amosba ? "Why ? "What various means 

 of dispersal has Parameoium ? 



Example 4. — The Bell Animalcule {Vorticella 8p.) 



Material. — Specimens of Vorticella may usually be 

 found in the water which contains Ammia and Para- 

 mecium. Fine examples are frequently found attached 

 to the stems and leaves of aquatic plants and to the fila- 

 ments of algse, also to shells and stones. 



Use the same apparatus, reagents, and stains as for 

 the slipper animal. 



Method of Examination. — The same as given for the 

 slipper animal. 



Use in general the questions and directions given for 

 the study of Paramecium, with, however, the following 

 additions, the omitted numbers indicating correspond- 

 ing parts of the two animals. 



Under Shape insert : — Look for colonies of Vorticella. 

 Are the individuals connected in any way ? Com- 

 pare the shape of the body and stalk in the ex- 

 panded state with the shape of the same parts 

 in the contracted condition. "What is the shape 

 of the body when seen from above? From 

 the side? Is the common name appropriate? 

 "Why? 



