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manifest. The cells forming these walls show coagulation necrosis, 

 hyaline degeneration, and more or less complete loss of their nuclei. 

 The perivascular concentric fibers are loosened and pushed apart 

 from each other by a leucocytic infiltration. The lumina of these 

 very much dilated vessels are crowded with apparently normal red 

 blood corpuscles, and with a slightly increased number of leucocytes. 

 Plague bacilli are not seen in the vessels. The original parenchyma 

 cells, the small mononuclears, show as a rule, a normal nucleus. 

 In some nuclei there is considerable pyknosis, while others are quite 

 poorly stained. Mononuclears, with large hyaline protoplasmic 

 bodies, are only rarely seen, plasma mast cells likewise are scanty. 

 The very numerous polynuclears are generally of the ordinary type, 

 a few are typically coarsely granular eosinophilics, while some have 

 an angular vacuolated protoplasm which does not show any granules 

 but stains very deeply with eosin. The infiltrating, extravasated 

 erythrocytes are mostly, to all appearances, normal; however, in 

 some places they have become agglutinated and confluent, almost 

 completely forming homogeneous masses, deeply staining with eosin. 

 No complete hyaline thrombi are found in the vessels, but a few 

 of the latter show an open network of fibrin. Such fibrin reticula 

 are also found here and there free between the cells. In the spleen 

 the pulp spaces show a considerable number of large, proliferated 

 endothelial cells. These appear to be derived from the lymphatic 

 endothelia lining the pulp spaces. They are generally phagocytic 

 cells, containing from two to twelve and more engulfed mono- 

 nuclears, polynuclears, and erythrocytes. The picture which the 

 pulp, with its many large endothelia, furnishes is much like that 

 seen in typical primary splenomegaly or splenic anaemia, but 

 the generally marked phagocytic character of the large pulp cells 

 is analogous to the condition found in the spleen in typhoid fever. 

 Plague bacilli are foimd very sparingly in the splenic sections. 

 Kidneys : The epithelial lining of the convoluted, as well as of the 

 straight tubules, is in an advanced state of cloudy swelling and 

 fatty degeneration. Some of the canaliculi contain a moderate 

 amount of granular matter. The glomeruli do not show any marked 

 changes. All of the vessels are much engorged and small sub- 

 capsular hemorrhagic areas are encountered. Liver: The veins 

 and capillaries are dilated and they contain much blood. The 

 protoplasm of the parenchyma cells shows fine, dust-like vacuola- 

 tion; their nuclei are generally well stained. Some of the liver 



