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condition of dilatation and engorgement of the vessels with general 

 cedema of the gland tissues has been established, diapedesis of -the 

 red blood corpuscles occurs; so that, as a rule, a lymph gland 

 infected to any extent with plague bacilli shows blood extravasation. 

 When the infection has become very extensive and the number of 

 bacilli very great, we generally encounter the most profoimd tissue 

 changes in the glands, associated with extensive blood extravasation. 

 To the naked eye a gland in this condition appears much swollen, 

 more or less softened, and from dark scarlet to brownish-red, with 

 yellow or yellowish-red mottling. Since the blood extravasation 

 extends beyond the gland proper, the periglandular tissue is like- 

 wise of a hemorrhagic color. The tissues in the neighborhood 

 of the gland are oedematous to a considerable extent. If the finer 

 histologic changes of the gland are studied, it is found that the 

 original tissue has frequently become necrotic; the differentiation 

 into cortical and medullary portions and into follicles and cords 

 is lost. The capsule of the gland has become loosened by oedema- 

 tous and cellular infiltration, and the latter extends far into the 

 periglandular tissue. Most of the original cells of the gland show 

 evidences of nuclear disturbances (pyknosis, etc.) and of coagula- 

 tion necrosis, and a large number of red blood corpuscles infiltrate 

 the entire tissue and invade the periglandular areas. The vessels 

 are greatly dilated and engorged and their walls are frequently 

 loosened by hydropic swelling and cellular infiltration ; or they may 

 be in a condition of more or less complete hyaline degeneration. Not 

 infrequetly one finds proliferated lymphatic endothelia in larger 

 numbers in the infected glands; these endothelia may or may not 

 show phagocytic properties, other cells or plague bacilli frequently 

 being included in them. Plague bacilli are often present in the 

 glands in dense zoogloeal masses. From such a center of enormous 

 infection the bacilli infiltrate the rest of the gland and the peri- 

 glandular connective tissue in more or less continuous groups. 

 In several of our cases we have seen in extensively infected and 

 hemorrhagic glands, a perfectly homogeneous vacuolated hyaline 

 material, which has a strong affinity for eosin and which we con- 

 sider a derivative of degenerating, agglutinated red blood corpuscles. 

 In fact, sometimes the derivation of the hyaline material from this 

 source becomes so obvious that there can be no doul)t of its origin. 



