TUBERCULOSIS. 455 



are gray striation s, alternating with the dark brownish-red 

 hyperaemic kidney-tissue and the engorged blood-vessels. In the 

 chronic form of this disease, on the contrary, the striation is of a 

 grayish-yellow color, and there is no hyperaemia whatever of the 

 kidney-tissue. 



One of the reasons which led to the statement that these 

 two varieties are different morbid conditions, was the difference 

 observed in the appearance of the consecutive atrophy. After 

 croupous nephritis this appears on the surface of the kidneys as 

 a coarse lobulation, with the formation of irregular elevations 

 and depressions of the cortical substance ; while after catarrhal 

 nephritis there is only a more or less uniform granulation and 

 shallow furrowing of the surface. The most striking proof is 

 furnished by kidneys which were in both poles in part attacked 

 by catarrhal and in part by croupous nephritis. The parts in 

 catarrhal inflammation exhibit fine granulation on the surface 

 and corresponding grayish-yellow striation of the nearly uni- 

 formly reduced cortical layer. In the portion attacked by 

 croupous inflammation the surface is coarsely lobular, and a 

 grayish-yellow infiltration prevails in both the irregularly 

 atrophied cortical and the reduced pyramidal layers. 



In the highest degrees of atrophy after catarrhal nephritis 

 the kidney is uniformly reduced to a half, a third, or even less, 

 its original size, yet still there is an indication of the striation of 

 the narrowed cortex, which blends, almost without a boundary 

 line, with the striated pyramids. The granulation of the surface is 

 very marked. After croupous nephritis in the highest degrees of 

 atrophy there are large nodes, separated from each other by deep 

 furrows, with an almost complete destruction of the cortical sub- 

 tance, and also a marked reduction of the pyramids, which are 

 pushed apart. In addition, there is a considerable amount of 

 fat at the periphery, and also at the hilus of the kidney, and a 

 more or less marked secondary waxy degeneration of the kidney- 

 tissue, which in some places may be reduced to a diameter of not 

 more than four to five lines. 



In both forms of nephritis, however, fatty and waxy degenera- 

 tion occur. Fatty degeneration in either produces a diffuse yel- 

 low discoloration of the kidney, and for the recognition of the 

 original morbid process the increased volume of the organ and 

 the aspect of its surface are decisive. I have observed high 

 degree of waxy degeneration after both kinds of nephritis, but 

 so far as my subjects of observation admit of a conclusion, I 



