anilin-water-fuchsin solution for a few moments, sections in the same solution cold for twenty-four hours; then immerse them first in a weak, then in a strong, solution of chlorid of iron. The cover-glasses are washed in water, sections in alcohol, and subsequently passed through the usual reagents for dehydration and clearing.

FIG. 60.-Bacillus of syphilis (Lustgarten), from a condyloma; x 1000 (Itzerott and Niemann).

In some syphilitic tissues these methods suffice to define distinct bacilli with a remarkable similarity to the tubercle bacillus. The organism is about the same size as, and even more frequently curved than, the tubercle bacillus, but often presents a club-like enlargement of one end (involution-form?). The bacilli very frequently occur singly, though more often in groups, and never lie free, but are always enclosed in cells. These bacilli are not always found in syphilitic lesions, nor is their demonstration easy under the most favorable circumstances. Lustgarten emphasizes particularly that they are only demonstrable after the most painstaking technical procedures.

The probability of the specificity of this organism was considerably lessened by the observation by Matterstock, Travel, and Alvarez that in preputial smegma, and also

in vulvar smegma from healthy individuals, a similar organism, identical both in morphology and staining peculiarities, could be demonstrated. Of course the occurrence of Lustgarten's bacillus in the internal organs could not but argue against the probability of its identity with the smegma bacillus ; but Lustgarten himself pointed out that the bacilli of both tuberculosis and leprosy stain by his method, and thus gave Baumgarten the right to suggest that the few cases well adapted for the demonstration of the Lustgarten bacilli might be cases of mixed infection of tuberculosis and syphilis.

The bacillus has not been isolated or cultivated, and its proper relation to syphilis is a matter which must be decided by future experimentation.

CHAPTER V.

ACTINOMYCOSIS.

IN 1845, Langenbeck discovered that the specific disease of cattle known as actinomycosis could be communicated to man. His observations, however, were not given to the world until 1878, one year after Bollinger had discovered the cause of the disease in animals.

Actinomycosis is a disease almost peculiar to the bovine animals, though sometimes occurring in hogs, horses, men, and other animals.

The first manifestations of the disease are usually found either about the jaw or in the tongue, in either of which

localities there are produced considerable enlargements which are sometimes dense and fibrous (wooden tongue) and sometimes suppurative. In sections of these nodular formations small yellowish granules surrounded by some pus can be found. These granules when viewed beneath the microscope exhibit a peculiar rosette-like body-the ray-fungus or actinomyces.

The fungus is of sufficient size to be detected by the naked eye. It can be colored, in sections of tissue, by the use of Gram's method, or better by Weigert's fibrin stain. Tissues pre-stained with carmin, then stained by Weigert's method, give beautiful pictures.

The entire fungus-mass consists of several distinct zones embracing entirely different elements. At the centre of the mass there is found a granular substance containing numerous bodies resembling micrococci. Extending from this centre into the neighboring tissue is a radiating, apparently branched, thickly-tangled inass of mycelial threads. These threads seem to terminate in a zone of conspicuous club-shaped radiating forms which give the colonies the rosette-like appearance. The cells of the tissues affected and a larger or smaller collection of leucocytes form the surrounding resisting tissue-zone.

The degree of chemotactic influence exerted by the organism seems to depend partly upon the tissue affected and partly upon the individuality of the animal. When the animal is but slightly susceptible, and when the tongue is the part affected, the disease is characterized by the production of enlargement due to the formation of cicatricial tissue. If, on the other hand, the animal is highly susceptible or the jaw is affected, the chief symptom is suppuration, with the formation of cavities. communicating by sinuses.

Before the nature of the affection was understood it was confounded with various diseases of the bones, principally with osteosarcoma.

From the tissues primarily affected the disease spreads to the lymphatic glands, and not infrequently to the

lungs. Israel has pointed out certain cases of human actinomycosis beginning in the peribronchial tissues, probably from inhalation of the fungi.

The occurrence of three distinct elements as components of the rays served to class this organism among the pleomorphous bacteria in the genus Cladothrix, where it has remained undisturbed for at least a decade. Recent researches have, however, changed the view held by some bacteriologists in regard to the actinomyces, and caused them to regard the organism as a bacillus. If it be a bacillus, the central zone of granular cocci-like elements is to be regarded as consisting of individuals in process of rapid division and spore(?)-formation, the mycelial zone as consisting of perfect individuals, and the peripheral zone, with the rosette-like, club-shaped elements, as consisting of individuals partly degenerated through the activity of the cells and tissue-juices (involution-forms).

Jones is of the opinion that the disease, if not indentical with, is closely allied to, tuberculosis, and that the occasional branched forms of tubercle bacilli prove the tendency of the individual bacillus to form a reticulum.

When the mycelial threads are carefully examined, the branchings, which appear distinct upon hasty inspection, are found to be more the effect of a peculiar relation which the threads bear to one another than actual bifurcations, so that it must be regarded as very questionable whether these threads ever so divide.

The organism may be grown upon artificial culturemedia, as has been proven by Israel and Wolff.

Upon agar-agar or glycerin agar-agar it forms translucent colonies, about the size of a pin's head, of firm, almost cartilaginous, consistence. These colonies consist of bacillary individuals, sometimes seemingly branched. In bouillon similar dense globular organisms can be grown. The blood-serum colonies, which grow similarly to the agar-agar colonies, are rather more luxuriant, and slowly liquefy the medium.