244 W. J. M. SCOTT 



mitochondria thick, often radiate from such a clump. These 

 usually extend parallel to the nearest margin of the cell, and the 

 mitochondria in them are oriented so that their axes correspond 

 in a general way with the direction of the strand. The cell on 

 the right shows two such strands running out from the large 

 mass of agglutinated mitochondria. In some cells almost 

 all the mitochondria are agglutinated in a single large mass, but 

 in others many scattered clumps of small size are formed. Where 

 there are large clumps of mitochondria those of them which are 

 usually distributed throughout the cytoplasm are greatly di- 

 minished in number. There seems to be a complete transition 

 between the condition of unclumped mitochondria (shown in 

 fig. 2) and these masses of agglutinated ones. Parallel with 

 agglutination of mitochondria there are other evidences of cel- 

 lular damage: the nuclei, instead of being sharp and clear, are 

 hard to define; frequently the nuclear membrane cannot be dis- 

 tinguished, the nucleoli are apparently absent ; and the cytoplasm 

 stains intensely as well as unevenly. 



In the next stage, that shown in figure 4, a noticeable change 

 is observed in the clumps above described. The agglutinated 

 mitochondria fuse together and lose their individuality. Figure 

 4 is the representation of a single cell which shows the transition 

 from agglutination to fusion. The triangular shaped mass just 

 above the nucleus is made up of closely packed, yet discrete 

 granules. It is a typical clump of agglutinated mitochondria. 

 The second large mass in the cell stains crimson with the acid 

 fuchsin just as the other does. Its outline, however, is roughly 

 spherical, but still somewhat irregular in shape, and it is impos- 

 sible to resolve it into separate mitochondria. It is not perfectly 

 homogeneous, though, for it shows evidence of its original granu- 

 lar nature. These two masses represent practically the entire 

 mitochondrial content of the cell although occasional scattered 

 mitochondria remain. It is possible to see in one section many 

 cells which illustrate well the agglutination as well as others 

 which show complete fusion. 



Figure 5 shows the results of a more severe intoxication with 

 phosphorus. The cells contain globular masses which bear a 



