CAUSE OF ACHROMASIA 59 



I shall now simply state the conclusions which were 

 arrived at then, subsequent experimentation not having 

 altered my opinion in any way. 



Achromasia seems to be part of the general dis- 

 organization which occurs in a cell after death. I have 

 never seen the phenomenon in a living cell, and one 

 cannot excite an achromatic leucocyte or lymphocyte. 

 It is by no means necessary for a cell to be stained 

 before it can become achromatic; on the contrary, one 

 frequently sees dead cells which refuse to stain, although 

 their living neighbours will stain well under suitable 

 conditions. The rapidity of onset of achromasia de- 

 pends upon the temperature and the presence and 

 amount of salts. It also appears to depend to some 

 extent on the completion of the liquefaction of the 

 cytoplasm. The more advanced the liquefaction, which, 

 of course, only occurs after death, 1 the more readily 

 does achromasia take place. Heat and salts accelerate 

 it greatly. If there are no salts present, even the 

 nuclei of ruptured cells do not become achromatic for a 

 long time. These stained nuclei may sometimes be 

 seen floating about free from cytoplasm, granules, or 

 cell- wall. I believe that achromasia is due to the 

 chromatin passing out of the dead and liquefied cell by 

 osmosis. If the chromatin is stained, the stain will dis- 

 appear with the chromatin ; if the cell is unstained, it is, 

 of course, impossible to stain its chromatin if the latter 

 has already passed out by osmosis. I believe that this 

 is what has happened in the cell which is commonly 



1 See paper in Journal of Physiology, "On the Death of Leucocytes," 

 vol. 37, No. 4, 1908. 



