14 LABORATORY DIRECTIONS IN 



of blunt pseudopodial processes. Such movements result in locomotion 

 or the engulfing of food. 



Id. Ciliary Movements. Paramecium. Examine specimens of Para- 

 mecium mounted on a slide. Note their movements. Introduce a small 

 drop of iodine along the edge of the cover-glass. The iodine kills the 

 animals and stains the cilia covering their surface. Study these cilia. 

 Approximately how much of the cell is devoted to ciliary movements? 

 Determine whether the whole surface is covered by cilia. Are the cilia 

 like the rest of the protoplasm or may they be regarded as specialized 

 for movement? 



Rotifers. Place a number of rotifers (wheel animalcules) on a 

 slide and examine with a microscope. Observe the ciliary movements 

 at the broader end of the body. Describe the structure and arrangement 

 of the cilia. Do they beat with equal vigor in both directions, or more 

 strongly in one direction? If the latter, is the form of the cilium during 

 the stronger beat the same as during the weaker one? If you detect a 

 differ ence., make a drawing of a single cilium to illustrate 'the difference. 



Gill of a freshwater mussel. 1 Mount a small piece cut from the edge 

 of the gill of a freshwater mussel. The epithelium covering the gill is 

 ciliated. As the piece slowly dies, the movements of the cilia diminish. 

 Observe their movements as in the rotifer. 



le. Flagellate Movements. Examine Euglena or Peranema on a slide 

 and note its form of locomotion. Introduce some iodine along the edge 

 of the cover-glass. Now look for specimens which have been killed by the 

 iodine. A long whiplike thread at one end is the flagellum by means of 

 which the animal moves. Flagellate movements are less common than 

 ciliary movements in tissues of higher forms. 



In which, if any, of the specimens so far studied is the moving proto- 

 plasm like the quiet protoplasm near it? In which, if any, does the moving 

 protoplasm appear to be differentiated for movement? 



2. Metabolism. 



2a. Ingestion. Mount some paramecia on a slide and note the 

 color of the round bodies (food vacuoles) in them. Put a small drop of 

 carmine suspension (well shaken) along the side of the cover-glass. 

 (India ink may be substituted for the carmine.) After a moment note 

 the formation of red vacuoles inside of the animal. The small carmine 

 particles have been ingested. Study a chart or model of Paramecium 

 and determine how ingestion is accomplished. 



26. Secretion and Digestion. Find a specimen on the above slide that 

 is quiet. To quiet them it may be necessary to press down the cover-glass 

 slightly or put them into a jelly made by steeping crushed quince seeds in 



1 The gill of a freshwater mussel may be used as a substitute for the rotifers or in 

 addition, at the option of the instructor. 



