After the intravenous introduction of a solution containing sodium chloride and urea into the rabbit during pronounced tartrate nephritis, all the chloride reappears in the urine within forty-eight hours. On the other hand, the nitrogen of the urine remains far below that usually eliminated by the normal animal under the experimental conditions; in other words, little or none of the urea injected is excreted by the kidney.
In the light of the histological findings these results are interpreted to mean that under normal conditions chlorides and water are passed through the glomerular mechanism, whereas urea becomes a urinary constituent by way of the convoluted tubules. These results constitute a direct confirmation of the older observations of others concerning the elimination by the kidney of the substances under discussion.
No evidence was obtained that the glomerulus may take over the function of the tubular epithelium.