CYTOPLASM AND NUCLEUS 



degree plastids may be spoken of in the same 

 way. 



But the bulk of Cytoplasma shows clearly by its 

 vital phenomena that it is principally transitory 

 structures such as are found in other colloids, 

 that occur there. A well-known fact is the 

 streaming of protoplasm. Streams of liquid 

 colloid matter wander in continual movement 

 through the different parts of the cell, carrying 

 with them different bodies, very frequently the 

 chloroplasts, and in some cases even the nucleus 

 itself. Very little is known about the reason for 

 this remarkable phenomenon. The general im- 

 pression is that surface tension plays a great part 

 in such plasmatic streaming. By continual change 

 of the chemical properties of the plasmatic surface 

 phenomena may result such as are seen in stream- 

 ing protoplasm. In any case, permanent structure 

 cannot be given in freely streaming protoplasm 

 which is continually moving in different parts 

 of the cell. Nevertheless, numerous chemical 

 changes of the greatest importance must take 

 place in the streaming polioplasma under the 

 same conditions which are found in other colloids. 

 Just in this territory the chemistry of Life may 

 hope to obtain results of the widest significance. 



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