198 COMMITTEE REPORT 



Thick, long, straight or curved threads, unbranched, fre- 

 quently clubbed at one end and tapering to the other. Gram 

 positive when young. Threads fragment into short, thick rods. 

 Anaerobic or facultative. Non-motile. Filaments sometimes 

 granular. No aerial hyphae or conidia. Parasites or facultative 

 parasites. 



The type species is Leptotrichia buccalis (Robin 1847) Trevisan. 



Genus 3. Actinomyces Harz 1877, p. 125 



Synonyms: Streptothrix Colin 1875, not Streptothrix Corda 1839; 

 Discomyces Rivolta 1879; Nocardia, Trevisan 1889; Micromyces Gru- 

 ber 1891, not Micromyces Dangeard 1888; Oospora Sauvageau and 

 Radais 1892; not Oospora Wallroth 1833; Thermoactinomyces Tsilinsky 

 1899; Cohnistreptothrix Pinoy 1913. 



Organism growing in form of a much-branched mycelium, 

 which may break up into segments that function as conidia. 

 Sometimes parasitic, with clubbed ends of radiating threads con- 

 spicuous in lesions in animal body. Some species are micro- 

 aerophilic or anaerobic. Non-motile. 



The type species is Actinomyces bovis Harz. 



Genus 4. Erysipelothrix Rosenbach, 1909, p. 367 



Rod-shaped organisms with a tendency to the formation of 

 long filaments which may show branching. The filaments may 

 also thicken and show characteristic granules. No spores. Non- 

 motile. Gram-positive. Do not produce acid. Microaero- 

 philic. Usually parasitic. 



The type species is Erysipelothrix rhusiopathiae (Bacillus rhu- 

 siopaihiae suis Kitt 1893; Mycobacterium rhusiopathiae Chester 

 1901; Erysipelothrix porci Rosenbach 1909), the causal organism 

 of swine erysipelas. 



Family II. Mycobacteriaceae Chester 1897, p. 63 



Parasitic forms. Rod shaped, frequently irregular in form but 

 rarely filamentous and with only slight and occasional branching. 

 Often stain unevenly (showing variations in staining reaction 

 within the cell). No conidia. 



