3. The existence of the altered epithelial cells, and the granular material resulting from their disintegration.

4. The pale colour of the Urine, and the presence of a small quantity of albumen. These characters point to the chronic nature of the case. The duration of the disease could not be ascertained, but from the number of casts containing epithelium, it was probably not of very long standing.

**The relative number of casts containing altered epithelium, is represented as much greater than was actually the case. Several extraneous matters have been copied in these figures, which are referred to in the explanation of the Plates.

PLATE XVI.

CASTS. ACUTE INFLAMMATION OF THE KIDNEY.

The casts represented in Plate XVI, are not very often met with. They are for the most part found in the Urine of patients suffering from an uncommon, and very acute, form of inflammation of the kidney, which often goes on to the formation of pus in the uriniferous tubes, and is sometimes fatal in the course of a few days. The structure of the tubes is completely destroyed, and a number being broken down, small abscesses are sometimes formed in the cortical portion of the kidney.*

In this case, although there was no history or other evidence of long-continued kidney disease, it is most probable that the man had been suffering from chronic nephritis for a long period, and that the structure of the kidneys had been seriously impaired before the occurrence of the acute attack.

I have seen recovery take place in two or three cases in which cells not to be distinguished from pus corpuscles

* See Dr. Johnson's work on Diseases of the Kidney.

PLATE XVII.

CASTS. CHRONIC NEPHRITIS.

a. Casts of large diameter, containing granular matter scattered through them unequally.

b. A very long, clear, and perfectly transparent cast, containing only a few oil globules here and there.

c. Dark granular casts, some of them containing a few oil globules.

d. Large masses of granular matter, many of them appearing like granular cells. Most of these are derived from the mucous membrane covering the glans.

e. Cells of renal epithelium, darker and more granular than usual.

f. Mass of squamous epithelium, probably from one of the follicles of the mucous membrane of the bladder.

g. Free oil globules.

h. Portions of cotton fibre.

i. Portion of feather.