CHAPTER XV. 

 TRICHOMYCETES. 



The trichomycetes or higher bacteria are intermediate in 

 morphological characters between the molds and the lower bac- 

 teria. They resemble the molds in the formation of long threads, 

 sometimes branching and interlacing to produce a network, and 

 in the formation of oval or spherical conidia constricted off from 

 the ends of the threads. They resemble the lower bacteria in 

 their small transverse diameter, the delicacy of their structure 

 and their mode of life. Petruschy 1 recognizes four genera, 

 Actinomyces, Streptothrix, Cladothrix andLeptothrix. 



Actinomyces Bovis. Bollinger in 1877 studied the lumpy- 

 jaw disease of cattle and described this parasite which occurs 

 in the lesions. Israel, in the following year, found the organism 

 in granulomatous lesions in man. The infection also occurs in 

 horses, sheep, swine and dogs. In the tissues and in the purulent 

 discharge from the lesions, the organism occurs in small yellowish 

 masses, sometimes visible to the naked eye but usually smaller 

 (10 to 2oo/* in diameter). Such a mass is a single colony of the 

 parasite or a conglomerate of several colonies. The colony is a 

 dense network of threads in the center, with radially arranged 

 threads about the periphery, most of the latter being swollen, 

 club-shaped, at their free ends. Spherical bodies may also be 

 present, but whether these are conidia or degeneration forms of 

 the parasite is uncertain. The organism is Gram-positive. 



Inoculation of pus or bits of tissue containing the parasite 

 from one animal into another usually fails to transmit the dis- 

 ease, although positive results have been obtained in a few in- 

 stances. Attempts at culture have failed also in many instances, 



1 Kolle and Wassermann: Handbuch, 1912, Vol. V, p. 270. 



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