Distentive Agencies in Growth of Cell. 109 



ended negatively. The so-called membranes are peripheral layers 

 resulting from the action of surface tension in masses of widely 

 varying composition under a wide range of external conditions. 



3. All of the substances known to promote growth which have 

 been tested have been found to accelerate hydration in living 

 cells, dead cell-masses and protein-pen tosan, — soap jellies at par- 

 ticularized concentrations from 0.0 1 M. to 0.000,01 M. and through 

 a range of P H from 4 to 11. Such action would represent the 

 action of young cells. The second phase of growth of the cell is 

 accompanied by the syneretic formation of vacuoles setting up 

 conditions, which have hitherto been interpreted in terms of 

 osmotic equilibria. 



4. The demonstration of the fact that polarizable separable 

 membranes are not formed, that the peripheral layer is not dom- 

 inantly proteinaceous, and that osmotic potentials are accumulated 

 in the cell far overbalancing that of the medium makes evident 

 the necessity for some new interpretations. 



5. The attempt is recorded to make up and operate an artificial 

 cell the outer wall of which should be a fixed colloid of clay, wood, 

 or parchment, and a lining or plasmatic layer of reversible gel, 

 simulating protoplasm, with a view to obtaining information as 

 to the accumulation of electrolytes in the cell with resultant 

 overbalancing osmotic potentials. 



6. Such cells filled with water and immersed in water show an 

 intake and excretion for a continuous period of 60 to 80 days at 

 1 5 0 C. during which time the vacuolar content of the cell is re- 

 placed two or three times. 



7. The artificial cell may be arranged to show exosmose in its 

 earlier stage, followed by endosmose, and negative osmose by the 

 action of calcium or magnesium salts as vacuolar contents or as 

 immersion media. Cells which have a tonicity equivalent to 

 0.003 M . potassium chloride when filled with water may be raised 

 to a tonicity of 0.005 M. by immersion in a series of increasing 

 concentrations, after a manner which has been Used in raising the 

 tonicity of living cell-masses. 



8. The course of metabolism, the action of light and the trans- 

 piration of water may be held to account for the concentration 

 of carbohydrates and electrolytes and the conversion of sugars 



