48 GENERAL BIOLOGY 



The following types, among others also available, afford 

 good material for such study. 



I. Protoplasmic Movement. 



1. Mount some of the healthy, younger leaves of Elodea 

 in water and with the high power examine their structure. 

 In the cells look for rather large green bodies, the chlorophyll 

 bodies. What is their form and how are they arranged in 

 the cells? These bodies float in a liquid, the protoplasm, 

 which is so transparent it is exceedingly difficult to see. 



Having noticed these features of structure look closely 

 for any signs of movement in the cell contents. The move- 

 ment is not rapid nor it is continuous, but you should observe 

 it in some of the cells of the young leaves. Make a draw- 

 ing of several cells, showing the chlorophyll bodies, and by 

 arrows indicate the direction of movement of the -proto- 

 plasm. 



2. Mount a cluster of leaves from the tip of the stem of 

 the stonewort, Chara or Nitella. The younger, more trans- 

 parent cells in this cluster should show the circulation of the 

 protoplasm very clearly. It will be necessary to focus 

 through the outer layer of the protoplasm w y hich contains 

 the chlorophyll bodies, the latter being stationary in this 

 form. Note the direction in which the protoplasm moves, 

 and whether all the cell contents are involved. Make a 

 drawing of the cell as seen with the high power, and indicate 

 by arrows in what direction the protoplasm is moving. It 

 may be possible to see the nucleus w r hich is carried along by 

 the currents. 



3. In the cultivated spiderwort (Tradescantia) the stream- 

 ing of protoplasm is beautifully shown. If the flower of 

 this plant is available take some of the hairs which are 



