ACTINOMYCETES. 367 



ACTINOMYCES BOYIS (also commonly known as strep- 

 tothrix actinomyces, actinomyces fungus, ray fungus) 

 was first observed by von Langenbeck in a case of 

 vertebral caries in 1845. According to Bollinger, the 

 fungus had been seen by Hahn a number of years before 

 in museum specimens, but had been regarded by him 

 as a penicillium. The name actinomyces or ray fungus 

 originated with Harz. It is constantly to be detected in 

 the tissues and exudates of the disease of cattle known 

 as actinomycosis, " lumpy jaw," " wooden tongue," etc. 

 The typical tumor of this disease is characterized by 

 inflammation, pus formation, excessive new formation 

 of connective tissue, abscesses, cavities, and sinuses. 

 Viewed as a whole, the tumor presents points of resem- 

 blance to the osteo-sarcomatous, the scrofulous or tuber- 

 culous, and the cancerous processes. The disease occa- 

 sionally occurs in man, and according to the point of 

 entrance of the parasite may arise in the mouth, the 

 pharynx, the lungs, the intestines, or the skin. In ani- 

 mals the disease is characterized by an excessive new 

 formation of connective tissue, so that tumefaction is 

 always a conspicuous peculiarity. In man, on the other 

 hand, suppuration is the most prominent feature. 



If the purulent discharge from an actinomycotic 

 tumor be examined fresh, it will be found to contain 

 tiny yellow (sulphur color as a rule) clumps. If these 

 be examined, unstained, in a drop of physiological salt 

 solution or water under the microscope, they will be found 

 to be made up of a rosette-like mass of closely inter- 

 woven threads. (See Fig. 65.) At the centre the mass 

 may show the presence of spherical, coccus-like bodies 

 or granules, while at the periphery the free ends of the 

 threads are more or less distinctly bulbous, or nodular, 



