MESENCHYME CELLS OF TISSUE CULTURES 443 



area. If the latter is true, we should not expect an increased 

 supply of oxygen to have as much effect upon it as it would if 

 it were a very active part of the cell and using a relatively large 

 amount of oxygen. 



SUMMARY 



Potassium permanganate produced a definite sequence of 

 changes in the mesenchyme cells, their rapidity depending 

 upon the strength of the solution. With a 1 to 40,000 or a 

 1 to 80,000 solution the changes were slow enough to be followed 

 and death of the cells occurred in about one-half hour. 



The nucleus was first affected and in a few minutes showed 

 coagulation changes that were followed by a contraction of the 

 chromatin material into a dense, pycnotic, deeply stainable 

 mass and the expulsion of the nuclear sap in the form of clear 

 fluid vacuoles. 



Shortly after the nuclear changes began the mitochondrial 

 threads broke up more or less into rods and granules and these 

 rounded up into vesicles. They probably became more fluid and 

 swollen and, since they are supposed to consist largely of phos- 

 pholipins, this indicated that oxidation had occurred as phos- 

 pholipins when oxidized take up water. The mitochondria if 

 previously stained with janus green or janus black no. 2 lost color. 



The degeneration granules and vacuoles also lost color if 

 previously stained with neutral red and the colorless granules 

 usually disappeared. The loss of these colors is an indication of 

 cell death. 



A condensation of some portion of the cytoplasm into a mass 

 which became finely granular and deeply stainable after fixation 

 often occurred. 



The centrosphere did not seem to be affected. 



There is a certain parallelism between these changes and those 

 which occur in mitosis. 



