204 Chalmers Watson, 



ing limb of Heiile may have already midergoiie an advanced degree 

 of disintegration; a pyknotic condition of the nuclei and subsequent 

 karyorhexis being very striking and constant associated phenomena. 



In the kidneys which are more gravely affected, the convoluted 

 tubules in the cortex are affected equally with the ascending limb of 

 Henle, and while some of the convoluted tubules show disintegration 

 of their cells (especially the tubules immediately subjacent to the 

 capsule), in others the change is more of the nature of a coagulation 

 necrosis. The collecting tubules are for the most part normal, but 

 in the more severe cases many of the smaller collecting tubules in 

 the cortex and medulla contain colloid casts which have been formed 

 by the fusion of necrosed secreting cells. 



The other structures of the kidney are affected to a much less 

 extent than the secreting tubules. The glomerular capillaries show 

 a varjdng degree of congestion; in the severer cases the capillary 

 walls are the seat of an acute hyaline swelling. The interstitial 

 tissue shows some degree of oedema and congestion of the inter- 

 tubular capillaries but no sclerosis. 



II. In the second series of observations on 5 castrated female 

 rats fed on a horse-flesh diet for 4 or 5 months the kidneys of two 

 of the Ave animals show no differences in structure from those of 

 the control subjects. In the remaining three the kidneys show an 

 early catarrhal nephritis, the lesion being most marked in the ascen- 

 ding limb of Henle's loop. The vessels appear normal, and there is 

 no indication of interstitial change. 



III. In the third series of observations on young animals fed oi 

 ox-flesh or horse-flesh, the kidneys of the ox-flesh fed animals ar 

 practically normal. In the three rats which were fed on horse-flesli 

 for 8 months the appearances are abnormal, the changes being of thi 

 same nature as those described in the first series, but much less ii 

 degree. In two of this series there are isolated accumulations of cells 

 of the lymphocyte type along the lines of the interlobular vessels. 



IV. In the series of observations on the second generation of 

 meat-fed animals (32) the kidneys of the majority show no patho- 

 logical change. A small minority in this series show changes corre- 



I 



