360 MICROBIOLOGY 



terized when growing in tissues by the formation of granules 

 which are stellately arranged threads projecting outwardly 

 with the ends club-shaped.* 



The actinomyces are the most important of the higher 

 bacteria. They produce the disease known as actinomycosis 

 which affects a number of species of animals including man. 

 Actinomyces seem to have been first observed by von Langen- 

 beck in 1845. 



CLADOTHRIX. 



This genus contains the threadlike forms in which false 

 branching may be recognized. By false branching is meant an 

 appearance resulting from the fragmentation of threads. The 

 terminal cell breaks away from the main stem, is set at an 

 angle by the elongation of the thread itself, and, as both con- 

 tinue dividing, the simulation of true branching is produced. 

 These forms occur largely in water and are not pathogenic for 

 animals. 



ACTINOMYCES BOVIS BOLLINGER. 



Place in nature. This species was discovered in cattle 

 by Bollinger ** in 1877. It was given the name Ac- 

 tinomyces or "ray" fungus by the botanist Harz. 

 Eivolta in 1878 described it as Discomyces bovis. In 

 1878, a similar organism was discovered by Israel l in 



* Those forms which do not produce rosettes with club shaped 

 rays in the tissues have been described as belonging to a separate 

 genus, namely, Streptothrix or Nocardia. If it is considered that 

 these forms constitute a different genus from actinomyces, Nocardia 

 should be adopted. Streptothrix was given to a genus of hyphomy- 

 -cetes by Corda in 1839 and the name is still used. 



** Bollinger, Deut. Zeit. f. Thiermed., Bd. Ill (1877) p. 41. The 

 disease produced in cattle by this organism had been known by a 

 number of names, that of osteosarcoma being the most common. 

 Bollinger, Perroncito and Johne made extensive investigations rela- 

 tive to the organism and the lesions it produces. 



1 Israel. Virchow's Archiv, Bd. LXXIV (1878) p. 15. 



