THE TRICHOMYCETES 150 



distinguished from the actinomyces by its pathogenicity 

 and cultural characters. It is not infective for rabbits, 

 does not form yellow or black pigment in cultures, and 

 does not liquefy gelatin. The cause of the black variety 

 is uncertain, but it is credited to a hyphomycete. 



Streptotrichosis. 



In addition to actinomycosis and madura disea.se, 

 other affections in which tubercles and suppuration are 

 involved are caused by Streptotrichece. The manifesta- 

 tions of some of these organisms strikingly resemble 

 and are apt to be mistaken for tuberculosis. Some 

 species, at any rate, are acid-fast and Gram-positive 

 when the filaments are young, but older or degenerate 

 threads are Gram-negative and not acid-fast. 



Streptotrichosis may affect the mouth, neck, lungs, 

 skin, kidneys, conjunctiva, appendix, and peritoneum. 

 Foulerton (Lancet, 1910, i., 551, 626, and 769) says that 

 cases show a preponderance of males, and the influence 

 of occupation and other circumstances involving special 

 exposure to the possibility of infection from a vegetable 

 source is very noticeable. Eppinger's streptothrix (St. Ep- 

 pingeri) belongs to Group II. of the Streptotrichecp, a 

 class possessing acid-fast properties, and showing more 

 active pathogenic action than the freely-growing species 

 of Group I. and the slow-growing species of Group III. 

 St. Eppingeri produces an infection which may be in- 

 distinguishable anatomically from a tuberculosis. 



The occurrence of branching forms in B. tuberculosis, 

 sometimes in typical actinomyces form, has led to a 

 suggestion that it should be placed among the Trichomy- 

 cetes. To quote Foulerton: ' There can be no reasonable 

 doubt but that at one stage of its growth the bacillus of 

 Koch is represented by branching mycelial threads of 

 the streptothrix type. And this being so, the common 

 " bacillary " forms represent the persistent rod segments 

 of a streptothrix.' Streptotrichece are commonly found 

 on grasses, and among the reputed bacilli which display 

 acid-fast properties are those having the characteristics 

 of a streptothrix Bacillus phlei I. and //. (Timothy- 

 grass bacilli), and the cow-dung bacillus (' Mistbacillus ') 

 All three are pathogenic for guinea-pigs but grow readily 

 on culture media. 



