L. =The Bacillus of Bubonic Plague.=--This was recently discovered by Kitasato, and, in view of the recent ravages of the disease in the Orient, has assumed considerable importance. It grows upon most media, and is found in the blood, in buboes, and in all internal organs of patients suffering from this disease. The smaller animals are susceptible upon inoculation. Animals fed with inoculated foods die also, showing the possibility of infection through the intestine. When exposed to direct sunlight for a few hours the bacillus dies. The general symptoms of the disease are those of hemorrhagic septicemia and its consequences. M. =The Bacillus of Rauschbrand.=--This is seldom, if ever, seen in this country. It is known in England as “the black-leg” or “quarter-evil.” It is an anaërobic organism, frequently met with in cattle, which causes a peculiar emphysema of subcutaneous tissue, spreads deeply, and is followed by a copious exudate of dark serum with gas formation. The smaller animals are not ordinarily inoculable; but if to the culture material there is added 20 per cent. of lactic acid, their insusceptibility is overcome and they succumb to the disease. So, also, as in the case of the tetanus bacillus, by addition of the bacillus prodigiosus or of proteus vulgaris the disease may be produced in otherwise insusceptible animals. N. =The Bacillus Aerogenes Capsulatus.=--The bacillus aërogenes capsulatus seems capable sometimes of causing pyogenic and even fatal infection. Its presence is associated with gas formation. It grows as an anaërobe. O. =The Bacillus of Chancroid.=--The bacillus of chancroid identified by Ducrey, and briefly described in the chapter on that subject. [Illustration: FIG. 7 Rhinoscleroma: infiltration of tissues about the nose. (Case reported by Dr. Wende, Buffalo.)] [Illustration: FIG. 8 Bacilli of rhinoscleroma. × 1000. (Fränkel and Pfeiffer.)] YEASTS. Busse was the first to call attention of clinicians and pathologists to the role played by yeasts in certain infections. Since the original observations of Busse in a case in which the organism produced a general infection, the lesions of which were a combination of tumor and abscess formation, various observers have noted the presence of pathogenic yeasts, usually in skin lesions. Gilchrist and Stokes were the first in this country to determine the nature of these organisms, and their observations have been followed by the detection of a large number of similar cases. In the skin lesions the organisms are found in minute abscesses; in the subcutaneous tissue and in the infections similar to those of Busse large abscesses surrounded by extensive masses of granulation tissue characterize the infection. The organisms can be detected in the pus by means of an examination of the fresh unstained fluid (Fig. 9). FUNGI.