PARAMECIUM 



(Materials: Carmine suspension, tannic acid, 15% alcohol, 

 cotton, filter paper.) 



Classification : Phylum Protozoa, Class Ciliata, Order 

 Holotricha. 



I. METHOD OF EXAMINATION. From an Assistant at the 

 preparation table get a drop of water from a culture containing 

 Paramecium. Place this on a slide with a few cotton fibers, 

 then add a cover glass. The fibers help retard the movements of 

 the Paramecia and thereby facilitate examination especially with 

 the high power. Examine with low power. From an Assistant 

 learn how to distinguish Paramecia from other Infusoria. 



II. GENERAL OBSERVATIONS. Describe the shape. Is it con- 

 stant? Is there a plane of symmetry? Anterior end? How deter- 

 mined? How does it differ from the posterior end? Is there a 

 dorsal (upper) and a ventral (lower) surface? Why? Notes re- 

 quired. With ocular micrometer find length and breadth of a 

 Paramecium. Make a model in clay showing the form of Para- 

 macium. 



The surface bearing the mouth is called the oral surface. 

 Make an outline drawing 60 mm. long, showing oral view. The 

 mouth should be about equidistant from the lateral margins of 

 the body in this drawing. The surface opposite the oral surface 

 is called the aboral surface. 



Draw lateral view in outline, 60 mm. long. 



III. STRUCTURES AND FUNCTIONS, i. Cilia are delicate pro- 

 toplasmic projections from the bodies of ciliates. Their detection 

 requires a very careful adjustment of the light through the mi- 

 croscope. Are they evenly distributed? Note the arrangement of 

 individual cilia as far as possible. Of uniform size? Do all 

 move? What functions ; do the cilia perform? Compare Amoeba 



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