170 HETEROGENETIC ORIGIN OP 



In a few days Dr. J. S. Collier kindly sent me a number of 

 sections, stained and unstained, which he had been good enough 

 to cut from the portion of the kidney in the formalin solution, 

 which I had handed over to him. Some of the sections sent 

 had been stained with methylene blue or with logwood, and 

 then mounted in balsam ; while I stained some of the plain 

 sections with gentian violet, and subsequently mounted them in 

 glycerine. On the whole, rather more details could be made out 

 with these latter sections than with the specimens mounted in 

 balsam. 



Every section, however, showed, inside the area which had been 

 affected by the chromic acid, that almost each cell within the 

 renal tubules was full of developing or actually developed Bacteria. 

 The former appeared as mere cocci-like particles which had taken 

 the stain like the developed Bacteria, both being situated in the 

 midst of cell granules comparatively unstained. The organisms 

 were distributed through the substance of the cells, but often 

 seemed to be most abundant in the half of the cell next the 

 wall of the tubule. In a few of the tubules in the pyramidal 

 portions of the kidney the organisms had developed more 

 abundantly, so that the cells were filled with a dense mass of 

 Micrococci such as may be seen in Fig. 3, A ( x 700). In sections 

 through blood-vessels also a moderate number of Bacteria were 

 seen mixed with the blood-corpuscles. 



Here, then, it is clear we have again the kind of appearances 

 which we have a right to expect if the microorganisms had developed 

 in the epithelial cells of the kidney by heterogenesis. We have 

 the cells full of particles developing into fully formed Bacteria, 

 and, what is more important still, we have them within almost 

 every epithelial cell to be seen in the sections. 



From the point of view of the wholly inadequate suggestion as 

 to organisms being found in such an abdominal organ as the kidney, 

 by reason of its " proximity to absorbing mucous membranes," it 

 may be well to recall the fact that the sheep's kidney is encased in 

 a mass of fat from half an inch to an inch in thickness, and that, as 

 an additional barrier separating wandering microorganisms from 

 the epithelial cells of the organ, there is still the thick and tough 

 capsule which I have thought it not useless to show in Fig. 3, B 

 ( X 700) — where it is represented, under the same magnification, by 

 the lower half of the figure. Let any one compare M. C, Potter's 

 description (p. 163) of the mod6 in which Bacteria are enabled to 



