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The infiltrating- cells are found around the interlobular arteries, 

 veins, and small bile duets. The small interlobular vessels show 

 a marked thickening of the adventitia, and most of the lumina are 

 found to be surrounded by a number of concentric rings, com- 

 posed of delicate connective tissue fibers. Occasionally there is 

 found a small vessel entirely occluded by an obliterating pro- 

 liferation of the lining endothelium. The cellular exudate of the 

 inflammatory foci consists of lymphoid cells and a high per- 

 centage of eosinophilic polynuclears. In some places the latter form 

 one-fourth to one-fifth of the total number of infiltrating cells. 

 Plasma cells are very sparingly represented. While this descrip- 

 tion conforms in general to most of the inflammatory foci in the 

 liver, other areas present decidedly varied appearances. In these 

 the foci, which are more or less nearly circular, clearly show a center 

 consisting of epithelioid cells with a vesicular nucleus and a large 

 protoplasmic body. Multinuclear giant cells are found in some 

 of the nodules. The histology of these round or oval nodules is 

 clearly that of the bacillar tubercle. The nodules also show a fine, 

 concentrically arranged, fibrillar network of connective tissue fibers. 

 Regressive changes are not seen. There is no caseation, nor does 

 Weigert's stain show any fibrin. The histology of the small 

 tubercules in the liver, and it may here he added that of the similar 

 structures found in the lungs, is identical with what has recently 

 again been described by Baumgarten as being the structure of 

 the tubercle experimentally produced and about two or three 

 weeks old, which has not yet undergone any regressive changes, 

 but in which the appearance of the first giant cells indicates that 

 the prolifieration of the tubercle bacillus, as well as that of the 

 inflammatory cells, has come to a standstill. Baumgarten also 

 describes the occlusion of small vessels by endothelial proliferation 

 brought about by the presence of the tubercle bacillus. The nodules 

 in the liver as well as those in the lungs contain an element which 

 is foreign to the typical uncomplicated tubercle, namely, numerous 

 eosinophilic polynuclears. It is impossible to prove the presence 

 of tubercle bacilli, but the tubercles are found to be infected with 

 the organisms of plague. The latter are seen here and there in 

 both types of inflammatory foci, in those which simply show the 

 structure of an ordinary inflammatory area, and in those possessing 

 the features of a bacillar tubercle. The parenchyma cells of the 

 liver exhibit a moderate degree of fatty degeneration. The capil- 



