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Further instances of bubonic plague are known to follow the bite of a plague rat. (Cases already reported by MAXWELL in his report on Plague in South China, CLARK in his Annual Plague Reports for 1900 and 1901, and SIMPSON in his recent Report on Plague in Hongkong. Cases have also been recorded in India.) Even the bites of plague stricken human beings have produced plague infection. (Aus- trian Plague Commission.)

In artificially infected animals, bubonic swellings are found. For instance after feeding animals with plague infected material, buboes may be found in the groins.

Mesenteric buboes are also met with in animals. Cervical, submaxillary and parotid buboes may be discovered, yet no injury of the buccal mucous membrane or carious teeth could be held accountable. The tonsils are held by many inves- tigators to be a channel through which the plague virus effects an entry. Great stress was laid upon this avenue of infection by the members of the Austrian Plague Commission. I have frequently examined the root of the tongue and tonsils and found marked edema of the mucous membrane of the tongue, enlarge- ment of the papillæ, great hyperemia of the lymphadenoid tissue and tonsils with extravasation of blood. The tonsils may be found twice or three times their nor- mal size. Plague bacilli have been found abundant in these situations. No evid- ence of such a mode of infection could be traced in experimental animals.

A careful dissection of these bubonic swellings shows us that they are much more extensive than is apparent from the appearance which they present clinically. For instance the bubo met with within the confines of Scarpa's triangle does not in a great many cases represent the focus of most intense pathological change. The bubo in Scarpa's triangle may be quite small. On cutting down on Poupart's liga- ment we find frequently a continuance of the hæmorrhagic extravasation around the inguinal glands. These are often somewhat larger than the femoral, and the pathological changes are more marked. Further dissection centrally leads us to the external iliacs in and around which one finds most intense lesions. The glands are larger, the dema widespread, necrosis may be present, and the surrounding extravasation of blood spreads in all directions, namely, over the ileo-psoas muscle reaching the crest of the ileum inwards to the true pelvis invading the broad liga- ment and its contents, and upwards along the iliac vessels to the aorta, spreading out like a fan over the muscles of the posterior wall of the abdomen and reaching the perirenal connective tissue and organs about the diaphragm. This bæmorrhage frequently joins another mass of blood which surrounds the coeliac glands. The latter are frequently enlarged, oedematous, and extravasates with blood, the group with surrounding haemorrhage forming a typical bubo. The condition of these cœlic glands is frequently overlooked in making post-mortem examinations on plague cases. The presence of such a lesion is of importance in regard to the gastro-intestinal avenue of infection in plague.

In the great majority of cases, the bubonic swellings are extremely painful. In groin buboes, the pain is located in Scarpa's triangle, often to a small swelling there, while the seat of greatest pathological change is really within the abdomen. This pain may be present for a considerable time previous to the detection of a de- finite swelling. The pain is probably of the nature of "Referred Pain" of Head.

All bubonic swellings, in my opinion, show the presence of extraneous micro- organisms. The infection with other bacteria would appear to occur early. The micro-organisms most frequently found present are, Staphylococci, Streptococci and B. coli and its varieties. The presence of these organisms appears to act deleteriously on the B. pestis. In advanced buboes these micro-organisms are even move numerous than plague bacilli.

In the majority of articles dealing with the bubonic variety of plague, it is stated that there is an absence of anything like a peripheral lymphangitis. The belief is widely diffused, that the infection takes place, in these cases, through the skin, but the B. pestis, in its passage from the focus of its entry to the seat of bubonic formation, does not excite inflammation. Beyond the possible discovery of the point of entry of the bacillus, therefore, there is no external evidence of the occurrence of such a bacillary infection through the skin. ALLBRECHT and GHON and many others, have laid down, that the absence of lymphangitis is characteristic for plague. Obvious reasons for such a statement do not, in my mind, appear to