36 



being enlarged and surrounded with sero-sanguineous extravasation, while 

 the other glands are either normal or merely enlarged or congested, in 

 this, the so-called septicsemic form, the affection of the glands shows itself 

 as a general involvement of all, or nearly all, of the lymphatic glands of 

 the body, although in many instances the affected glands were chiefly 

 those of the mesentery. In no case, however, did the involvement proceed 

 to the formation of the characteristic plague buboes, but only to a moderate 

 degree of change, practically restricted to the glands themselves, but still 

 displaying in several of them certain distinctive features. These were 

 moderate enlargement and cedema without much congestion, the glands 

 being pink in color, firm and rounded, and with a soft interior, often 

 possessing here and there small areas of softening surrounded by firm 

 substance. Several of the affected glands may be thus modified, while 

 others of them are merely enlarged and engorged with blood, thus resembling 

 the less affected glands of ordinary Pestis major. Excepting the lymphatic 

 glands, the parts that were affected showed essentially the same pathological 

 changes as in the biibonic variety of Pestis major, but usually the number 

 of parts affected was smaller and the degree of change in them was 

 less. 



Pestis pneumonica or pulmonalis, or primary plague pneumonia. — Inflam- 

 mation of the lungs occurs, as already stated, with considerable frequency 

 during the course of the plague, and it then becomes a serious complication. 

 It also occurs so early in the disease as to justify the belief that the 

 plague virus had affected the lungs either primarily or coincidentally 

 with the more general affection of the body, thus constituting a form of 

 plague which is distinguished as primary pneumonic plague. When con- 

 trasted with those occurring in Pestis major, the pathological changes 

 elsewhere than in the lungs are less intense. While those in the lungs 

 are more intense. The lymphatic glands are only slightly affected, and 

 external buboes having the characteristics seen in Pestis major are seldom, 

 if ever, encountered. Congestion and enlargement of organs and even 

 hemorrhage in mucous and serovis membranes may be present, but they 

 do not assume the proportions attained in Pestis major. On the other 

 .hand, the lungs are conspicuously affected. The whole substance is en- 

 gorged, the large as well as the small blood vessels being distended; and 

 hemorrhagic zones are seen scattered throughout the lungs, filling the 

 alveoli and often breaking do^Ti their walls. Within the hemorrhagic 

 zones are areas in which the alveoli are completely filled with leucocytes, 

 epithelial cells and granular debris, constituting, with the surrounding 

 zones of hemorrhage, blood-congested areas of catarrhal pneumonia. In 

 these areas, as well as in the fluid matter contained in the trachea and 

 bronchi, plague bacilli are abundantly present. Greyish necrotic patches 

 have also been found containing large numbers of plague bacilli. The 

 bronchi are engorged with blood, and catarrhal cells are found in their 

 terminations. Over affected areas at the surface of the lungs, the pleura 

 may be acutely inflamed. In most cases, the bronchial glands were con- 

 gested, and there was a little hemorrhage into the gland substance; but 

 in some cases, their appearance was normal. 



