LEO LOEB AND KENNETH C. BLANCHARD. 2Q7 



different parts of the tissue. Neither heating nor a preliminary 

 treatment of the tissue with acid and alkali alters this result. 



4. We conclude from these experiments that vital stains may be 

 taken up by cells in two forms, (i) through the electrostatic 

 forces of primary or secondary valencies they may be attached to 

 the granules or to the cell protoplasm, or, (2) they may be present 

 in a solution in circumscribed areas of the cell. In the latter 

 form they behave towards environmental factors in a way similar 

 to solutions of the stain. It is possible that also the acid vital 

 dyes exist in the latter form, whenever they are taken into a cell. 



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