OSMOTIC GROWTH 



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one. During the first period their specific gravity is greater 

 than that of the surrounding medium, and thev rest immobile 



Flc;. 52. — Amoeboid osmotic growth with long crystalline cilia swimming 

 about in the mother liquor. 



at the bottom of the vessel in which they are sown. As thev 

 grow, they absorb water and their specific gravity diminishes. 



FlG. 53. — Osmotic growth swimming in mother liquor. The I'm like pro- 

 longation grew out between two liquid layers of different concentrations. 



Little by little thev rise up in the liquid, and finally acquire 

 a considerable amount of mobility, being readily displaced by 

 every current. Hence it is very difficult to photograph these 



