﻿ETIOLOGY OF MYCETOMA. 483 



the outer membrane appears to be irregular in thickness and density and 

 absent in places; the inner portion is also frequently and irregularly 

 broken, and thus the appearances of bacillary and ovoid or coccal sections 

 is produced. Branching forms are plentiful, the branches first appar- 

 ently appearing as buds, which grow to hyphge from the side of the 

 mycelial thread. True dichotomous division has not been observed. 

 The small, round bodies mentioned above often appear to have a double 

 containing wall and they vary in diameter from 3 to 10 p. 



Staining. — The Streptotlirix takes the majority of the ordinary stains 

 in preparations of fresh material; it is stained by the G-ram-Weigert 

 method, and its acid-fast and alcohol-fast properties are quite marked, 

 particularly in the older filaments. 



The Ziehl-Neelson-Gabbet method for staining the tubercle bacillus 

 is also very satisfactory for Streptotlirix freeri, the fungus elements 

 assuming the same bright red color which is imparted to tubercle bacilli. 

 The structure of the granules becomes fairly apparent by the various 

 methods of staining and the specimens confirm the observations already 

 recorded when discussing the fresh materials. 



Stained specimens which show the individual elements give some 

 interesting results. Some specimens, when they are colored by the 

 method used for tubercle bacilli, contain so many of the bacillary forms 

 which take the red stain and which closely resemble Bacillus tuberculosis, 

 that we at first thought the latter organism was also present in our 

 cultures. However, further study has shown these, as well as the coccal 

 and other irregular forms, to result from the breaking up of the older 

 mycelial filaments. These bodies which resemble tubercle bacilli may 

 sometimes be seen in the filamentous mycelia, still surrounded by the 

 unbroken sheath. 



Cultures. — Cultures on agar and glycerin agar, from the open wounds 

 before amputation and after the foot had been dressed for twenty-four 

 hours in a wet bichloride dressing, remained sterile. The Streptotlirix 

 was cultivated without difficulty from the sinuses and tissues of the 

 amputated foot and no bacteria were present except when the cultures 

 were taken from those surfaces contaminated by the knife in opening 

 the foot; in the latter instances saprophytic bacteria were also present. 



Lesions from which the Streptotlirix was obtained in pure culture 

 were produced in monkeys after the inoculation of fresh material. 

 The microorganism is aerobic and it grows with greater or less readi- 

 ness upon most of the ordinary laboratory media. Cultures upon media 

 containing sugar or glycerin and upon potato have some color, which 

 varies in intensity. 



A profuse growth appears in a few days in certain media, but in others 

 the development is much slower. Potato, sugar containing media, and 

 glycerin agar at 37° C, are best adapted to the growth of the fungus, 



