158 GENERAL SYSTEMATIC BACTERIOLOGY 



dans les vieilles cultures, principalement en bouillon addition^ de serum aggluti- 



nant, on trouve souvent des formes d'involution les plus bizarres 



Jamais on ne trouve de filaments dichotomises comme les autres actinophytoses 

 deja signales ici. 



Enlows (1920, p. 11) gives the following characterization: 



Pleomorphic. Sometimes rodlike, sometimes coccuslike, in pairs; also strep- 

 tobacillary forms occur: 0.15/^ to 1.25/i in length by 0.4/i; non-motile: no spores; 

 gram-negative; bipolar staining. The final stage of growth gives rise to little 

 masses, in which the organisms are pressed closely together, giving the ray like 

 aspect. These masses consist of a central germinative zone and an outer or 

 vegetative zone. Cause of actinobacillosis in cattle. 



This is to be regarded as a casual name for the genus Aciinobacillus. 



Actinobacillus. A generic name given by Brumpt (1910, p. 849) 

 to the organism causing "Actinobacilosis" and termed "Actinobacilo" 

 by Lignieres and Spitz (1902, p. 1G9). The organism was accorded no 

 specific name by Lignieres; it was named by Brumpt in his honor, 

 Actinobacillus Lignieresi. This species therefore constitutes the generic 

 type. 



The organism is the cause of an infection in cattle and sheep termed 

 actmobacillosis. The lesions resemble closely those of actinomycosis. 

 In culture of the organism on solid media small, transparent colonies 

 appear in twenty-four hours. They consist of small diplococcus-like 

 bacilli or of streptobacilli, resembling the fowl cholera organism when 

 grown in broth in their occurrence in long chains. Dextrose and lactose 

 are not fermented. Indol reaction is weak. The pus in the lesions 

 contains granules the size of a millet seed. Microscopically these show 

 at their peripheries swollen, finger shaped, branched forms whose 

 central ends are pointed. The filaments are Gram-negative. The 

 central portion does not contain a branched mycelium. Isolated 

 threads are not found in the pus. 



Enlows (1920) states "Type species (monotypy). A. lignieresi. 

 Streptobacillary^ bacillary or coccoidal in form. Gram-negative. 

 Never filamentous." 



Merrill and Wade (1919, p. 64) state that this name was given to a 

 supposed subtype of Discomyces; but that the distinction has not been 

 recognized, and by most authors the name is considered a synonym. 



Buchanan (1918, p. 404),Winslow et al. (1920, p. 198) and Bergey 

 et al. (1923, p. 338) recognize the genus with the following diagnosis: 



Filament formation, resembling streptobacilli. In lesions no mycelium is 

 formed, but at peripheries finger shaped branched cells are visible. Gram neg- 

 ative. Not acid fast. 



