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proportion of the Bubonic variety is noteworthy. That there is direct infection anu inoculation by abrasions and wounds of the skiu there is no doubt, and it must not be forgotten that it is quite possible for direct inoculation to take place. through small wounds whose presence may be lost sight of or may remain un- detected. A reaction at the seat of inoculation may not always occur—the in- fective material may be absorbed and conveyed by the lymphatics to the nearest chain of glands without showing that they (the conveying vessels) are affected in any way. In this way the infection may be carried to the more superficial glands or to the deeper over. These glands act as a sort of reservoir in which the bacilli accumulate, practically stagnate and partly die; and should necrotic changes be set up they are entirely destroyed and rendered powerless. During this period they elaborate the protein poison which rapidly diffuses through the lymph channels, is taken up by the circulation and acts in the direction of paralysing the vasomotor nerves, thus leading to hæmorrhagic effusions, to dilated blood vessels, and to a dilated and debilitated heart. The principal channel of infection. then being the skin it is not difficult to understand on reference to Table VI that most glandular swellings were to be noticed in the femoral region--31; and in the inguinal region-11, and in both femoral and inguinal regions-7-point- ing to infection through that part of the body most likely to come into contact with infectious material, the lower extremities. Glandular swellings in the axillary region occurred in three cases, in the cervical region in 4 cases, and in the cervical region in combination with the femoral region in 2 cases. These cervical buboes I attribute to primary infection of the tonsils which in such cases were enlarged and painful.
The Diagnosis of Plague.-Since we have become familiarise with using for diagnostic purposes a thick blood film decolourised and stained with a basic dye, as was first adopted here by Dr. BELL, there scarcely has been any hesitation in naming as the Plague bacillus all organisms that shewed a bipolar reaction, and diagnosing as Plague any case in whose blood films, prepared thus, these organ- isms were found. Such a method of diagnosis is far too summary. This cannot be too strongly pointed out and insisted upon. Bipolar organisms, fairly commonly distributed, exactly like the bacillus pestis microscopically, are very easily mistaken for it. Should a patient present the clinical symptoms of Plague and a bipolar organism be discovered in the blood we might safely infer without further tests that it is the Plague organism. Should on the other hand a bipolar organism be found in a blood film or a smear, and the person shews no other sign suggestive of Plague the presence of the organism is most evidently a contamina- tion. Cases have been diagnosed as Plague from the presence of this bipolar organism in a blood film without especial reference to clinical symptoms, and mistakes have occurred even when the greatest pains and care have been taken to avoid the possibility of contamination. The diagnosis of Plague is a very import- ant matter and should be based upon a clinical as well as a bacteriological diagnosis, and not upon a microscopic diagnosis alone. In the case of the lower animals equally great care should be taken, and no positive opinion can be accepted unless every bacteriological test has been thoroughly worked out and experimental proof obtained. Otherwise the diagnosis not only violates scientific deductions and accuracy but what is perhaps an equally grave matter it causes a scare with regard to fresh sources of infection. It should therefore be recognised that the presence in a blood film or smear from any tissue or organ of a bipolar staining organism does not necessarily mean per se that that organism is the bacillus pestis. During an epidemic of Plague or when the patient presents the clinical symptoms of the disease we may safely conclude that bipolar organisms found in such films are true bacilli pestis, assuining of course that every care and precaution has been taken in making the film so as to avoid contamination. On the other hand the absence of the bacillus pestis from such films does not negative the diagnosis of Plague when clinical symptoms are present..
The Distribution of the Bacillus Pestis.-It is generally accepted that the bacillus pestis is found in the peripheral blood immediately preceding death, but later researches here shew that it may be found also at any time during the course of the illness, thus demonstrating the presence of the bacilli in the general blood stream practically immediately after infection. During the course of the year I paid some attention to this point and was struck with the varying results obtained, which I have summarised in Table No. X and which I shall briefly note here.. I may promise that all the cases examined presented the classical clinical symptoms of Plague and that repeated examinations of slides were made in each case.