DIFFUSION- VACUOLES 



believe the reason for this is, that when the droplet of 

 liquid becomes suspended in the jelly-like cytoplasm 

 it forms a cavity in it, and the walls of the cavity 

 actually become stained. This is readily seen when 

 the vacuoles disperse, for portions of the stained wall 

 of the cavity can be demonstrated. When cytoplasm 

 is wounded (the formation of a vacuole in it really con- 

 stitutes a wound of it) the cytoplasm stains deeply with 

 an anilin dye, and this appears to be the reason why the 

 "red spots" seem to be so deeply coloured. Moreover, 

 being spherical droplets, they are highly refractile. 



We have never seen diffusion-vacuoles in normal 

 cells immediately after they have been removed from 

 the body; it is always necessary to induce them. 

 There is an exception to this rule, however, in the 

 cells of some malignant growths, especially cancer of 

 the breast, in which we have frequently seen large 

 "red spots." We think that it is possible that the 

 injured cytoplasm associated with these spots may 

 produce the deeply staining patches which have been 

 described as "archoplasm" in these cells when they 

 are fixed and stained by the older methods. In a 

 former paper we also suggested that archoplasm might 

 be derived from chromatin which has diffused through 

 the cytoplasm to some extent, and we still think that 

 this may be possible, but it is also probable that archo- 

 plasm is derived from the fixation of injured cytoplasm 

 connected with a dift'usion-vacuole. We have never 

 seen anything like the commonly described archoplasm 

 in a normal living leucocyte, and it certainty does not 

 play any role in their cell-division. 



