The modes of infection with the bacillus of the plague are as follows: (1) By inoculation. The history of the present epidemic in Asia recounts several instances of inoculation with the plague bacillus. On June 22 or 23, 1896, while making a post-mortem examination, Professor Ayoama, of Tokio, one of the Japanese commissioners sent to Hong Kong to study the plague, scratched the third finger on his left hand; on June 27th he again scratched himself on the end of the right thumb; on the evening of June 28th he felt ill, and had a temperature of 101.6° F.; he slept well during that night, but during the afternoon of June 29th he had a temperature of 105° F. At that time a bubo was found in the left axilla, and there was well-marked lymphangitis of the right arm. Professor Ayoama has described his own case as follows: "On June 28th, after having finished a dissection, I took my meal about half past two and did not enjoy it. After the meal I went upstairs, when at certain movements of the arm I felt a slight pain in the left armpit, and on feeling with my finger I found some slightly enlarged glands present. In the evening I felt very ill, depressed, and languid, burning hot along the whole of the back, while the thermometer showed normal temperature. As Mr. Kitasato and I had invited guests that evening, I was present at supper. I had no appetite, and felt so languid that I often wished to withdraw. At half past eleven I hurried to my room, when I found my temperature was 39° C. I took one gramme of quinine, and slept well. Next morning I awoke and noticed, on the under side of the left ring finger, a small, whitish-yellow blister, and then, along the back of the hand, a red line. From this time I remembered nothing for more than two weeks." Dr. Ishigami, another of the Japanese commission in Hong Kong, also inoculated himself with the plague while making a post-mortem examination. A patient, while delirious with the pneumonic form of the plague, expectorated into the face of an English nurse caring for him. Within a few hours the eye on that side of the face became inflamed; later the parotid and cervical glands became involved, and the nurse died. Other illustrations of inoculation with the bacillus of the plague might be given. Dr. Wyssokowitch and Dr. Jobobat believe that the bacillus can penetrate the unbroken skin. In support of this belief they report some experiments made by them upon macaque monkeys. They found that when a needle was dipped in the culture of the plague bacillus and drawn across the palm of the hand of one of these monkeys, without making any visible scratch, the animal speedily developed the disease. However, this does not prove that the bacillus will penetrate the unbroken skin of man. (2) By inhalation. That the pneumonic form of the plague results from inhalation of the bacillus can not be doubted. Monkeys caused to inhale the bacillus develop this form of the disease.