Chapter XI — 175 — Human and Animal Diseases 



bic conditions in the form of small white flakes, some floatina and some 

 collected at the bottom of the tube. Growth was better under anaerobic 

 conditions. 



In smear preparations from agar cultures, the organism appeared 

 chiefly as short, homogeneous, usually straight, but also comma-like or 

 bowed, rods of varied length and width. The ends of the rods often 

 showed club-like swellings. Microscopically the growth was charac- 

 terized by development of long filaments forming a network. The 

 longer filaments were arranged more or less radially; they were straight, 

 wavy, or spiral, and sometimes branched. 



On autopsy, infected animals showed tumor growths mostly in the 

 peritoneal ca\'ity and in one instance in the spleen. The tumors were 

 situated partly on the abdominal wall and partly on the intestines, in 

 the liver, and in other tissues. Microscopic examination of the tumors 

 showed in all cases but one the presence of typical actinomyces colonies, 

 in most cases with typical "clubs." The general histological appear- 

 ance of the tumors was like that of actinomvcotic tissue. 



Simultaneously with the work of Israel and Wolf there appeared, 

 in 1890, a contribution by Bostroem (44) reporting his isolation of an 

 aerobic organism, which he considered to be the same as A. hovis Harz 

 but which was later believed to be a saprophyte. Bostroem's theories 

 were supported by Pinoy (339) and by others who suggested the occur- 

 rence of two forms of actinomycosis in cattle, one caused by anaerobic 

 forms, and the other by an aerobic species. Careless isolation tech- 

 niques and erroneous identification of isolates added to the confusion. 

 Aerobic strains of several tjq^es mislabeled A. hovis gradually found their 

 way into the culture collections of the world, and came to be known as 

 A. hovis (349). Since these strains grow readily, they survived where 

 strains of the anaerobe died and became permanent sources of confusion. 



Berestneff (32) differentiated actinomycosis from pseudo-actino- 

 mycosis. The first was considered to be typical, in the sense described 

 by Bollinger and Harz and by Israel and Wolf, The second was 

 looked upon as an atypical form and was believed to be caused by vari- 

 ous gram-positive and gram-negative bacteria and by those actinomycetes 

 to which the aerobic form of Eppinger and others belongs. Berest- 

 neff looked upon A. hovis and A. hominis as collective names, and be- 

 lieved that actinomycosis is caused by various actinomycetes. Only in 

 very few cases was a single actinomyces found to be responsible for 

 clinical actinomycosis; in most others, a complex population, the mem- 

 bers of which belong to the anaerobic flora of the mouth (137), was 

 said to be responsible for the infection. 



NocARD first described, in 1888, a pathogenic actinomycete of the 

 aerobic type. This organism was found to be the case of "farcin du 

 boeuf," a disease of cattle in Guadeloupe Islands. De Toni and Tre- 

 vi^AN, in 1889, designated the aerobic organism Nocardia, in honor of 

 its discoverer, the species being N. farcinica (324). In 1890, Eppinger 



