1889.] MICROSCOPICAL JOURNAL. 101 



4th. Bacilhis. — Fine filament, straight or bent. 



B. of anthrax. 



B. of malignant oedema (horse). 



B. of glanders. 



B. of tuberculosis. 



B. of septicaemia. 



B. of swine plague. 



B. of carious teeth. 



B. of leprosy. 

 jt/i. Vibrio. — Wavy, flexible filament. 



V. of emphysematous anthrax (black-leg) . 



V. of septicaemia. 



V. of cholera (comma bacillus). 

 6th. Spirillum. — Spiral, rigid filament. 



S. of relapsing fever (horse). 



S. of milk-sickness. 



S. of gums and teeth (spirochcete cohni). 



Actinomycosis.* 



By C. T. CALDWELL, M. D., 



WASHINGTON, U. C 



It is only within a few years that attention has been called to the dis- 

 ease which bears this name, or more correctly speaking to its true char- 

 acter, as distinct from osteo-sarcoma, with which it was confounded, 

 until Bollinger in 1S77 studied the disease in cattle, and for the first 

 time described the fungus and made known the nature and cause of the 

 malady. 



The disease appears to be far more common in cattle than in other 

 animals, and begins usually in the alveolar processes of the jaw, where 

 it may first be detected by the presence of small nodular growths from 

 the size of a pea to that of a walnut. These growths may be few or 

 many in number. They have a tendency to spread or increase in size 

 until they coalesce and form large hard tumors attached to the bone. 

 This appearance led to the supposition that the disease was a form of 

 osteo-sarcoma and was supposed to affect no other part than the jaw 

 and no other than the bovine species. Its presence in other parts of the 

 body and in other animals has since been frequently shown, although 

 cattle and pigs seem to suffer most, and the jaw is the starting-point in 

 a great majority of cases. Its appearance in man is rare. The number 

 of recorded cases from 1878, when the first case was reported, up to 

 1S85 had not exceeded 20 in all, most of these happening in Europe, 

 no case having been reported in the United States up to that time. 

 During the past three years, however, a larger number of cases have 

 been found, until now the recorded cases number about 100 all told, of 

 which a few have occurred in this country. 



With this brief sketch of its history let us look a little deeper into the 

 subject and study more closely by the aid of our microscope the para- 

 site which is the cause of this disease, ascertain if possible its nature, 



* Read at the 86th meeting of the Washington Micioscopical Society. 



