LIVER CELLS FROM CHICK EMBRYO 295 



Granules in active Brownian movement were observed in most 

 of the vacuoles; in a few none could be made out. The first 

 granules to appear in the vacuoles were small and single; as the 

 culture aged the granules within the vacuoles increased in size 

 or in number, or both. In some older cultures a large number 

 of small granules were sometimes present in a vacuole; in most, 

 however, there were two or three large irregular masses to a 

 vacuole. All of these bodies showed active Brownian motion 

 as well as more extensive moving about within their enclosure. 



The early vacuoles appeared in any part of the cell midway 

 between the nucleus and the cell edge, in contact with neither. 

 As they increased in number they remained grouped about the 

 nucleus so that in the marginal cells there was a clear edge of 

 normal appearing cytoplasm with a proximal mass of vacuoles 

 surrounding the nucleus (fig. 25). Their increase in size and 

 number continued until finally the whole cell was changed into 

 a foamlike mass surrounding a more or less distorted nucleus 

 (fig. 23). At this stage the cell stained very deeply with neutral 

 red. Eventually the whole growth fragmented and broke loose 

 from the coverslip, what was left of the degenerated cells being 

 represented by small, granular, irregular masses no longer 

 showing any signs of vacuolization and floating free in the 

 medium. 



In a few untreated degenerating cultures, and in those treated 

 with potassium permanganate or janus green, the fluid in the 

 degenerating cell did not form vacuoles throughout the cell 

 substance but collected along the periphery, forming clear blebs. 

 In the untreated cultures this form of degeneration occurred a 

 little later than the average time for vacuolization; bleb forma- 

 tion was not observed in any untreated cultures before the fourth 

 day of cultivation and many cultures did not show it before the 

 seventh day. In some cultures treated with potassium perman- 

 ganate blebs formed within five minutes after treatment ; in those 

 treated with janus green, blebs appeared in a half to one and a 

 half hours after the addition of the dye. 



The first indication of this type of degeneration was the con- 

 traction of the cells. A few minutes later clear spaces appeared 



