CLASSIFICATION 381 



Actinomyces. 



A. Predominantly anaerobic types. Actinomyces hovis Harz. 



B. Predominantly aerobic types. 



(1) Non-acid-fast. Actinomyces graminis Bostroem. 



Actinomyces caprcB. 

 Actinomyces madurce. 

 Actinomyces somaliensis. 



(2) Acid-fast. Actinomyces farcinicus. 



Actinomyces asteroides. 

 Actinomyces gypsoides. 



C. Facultative aerobic types. Actinomyces mtiris. 



The creation of a special subdivision for the facultative aerobic types is dictated, 

 partly by convenience, and partly by the differences of the main species Actinomyces 

 muris from the anaerobic Wolff-Israel type. 



There seems little doubt that the organism Streptohacillus moniliformis, to 

 which so much attention has been called in recent years by Levaditi, Nicolau, 

 and Poincloux (1925), Parker and Hudson (1926), Levaditi, Selbie and Schoen 

 (1932), Strangeways (1933), and Mackie, van Rooyen, and Gilroy (1933), is the 

 same as the organism isolated by Schottmiiller (1914), Blake (1916), and Tileston 

 (1916), from one tyjDC of rat-bite fever in human beings, and called Streptothrix 

 muris ratti. Since the original name for this organism claims priority over Strepto- 

 hacillus moniliformis, we propose to adopt it. Modification, however, is necessary, 

 partly to suit the binomial nomenclature, and partly because the term Streptothrix 

 is not valid. In its place we suggest the name Actinomyces muris. 



The inclusion, however, of this organism in the Actinomyces group is admittedly tenta- 

 tive, and may well have to be revised in the light of future work. The observations of 

 Kheneberger,ofDienes,ofHennian and others (see pp. 939, 945) have revealed the existence 

 of a group of small pleomorphic bodies resembhng in many ways organisms of the pleuro- 

 pneumonia group. The first of these bodies was isolated from a culture of Streptohacillus 

 moniliformis. Whether it was a variant form of this organism or a symbiont remains 

 doubtful, but since the other pleuropneumonia-Hke bodies that have been described do 

 not appear to have been associated with Streptohacillus 7nonHiformis, it seems premature 

 to transfer this organism to the pleuropneumonia group and call it, as Heihnan (1941) 

 suggests, Asterococcus muris. We propose, therefore, to include it temporarily at least 

 in the Actinomyces genus, but to describe the pleuropneumonia-Uke bodies associated with 

 it in the chapter on the pleuropneumonia organism and associated forms. Van Rooyen 

 (1936) would exclude Streptohacillus monilifortnis from the Actinomyces group, because 

 he was unable to demonstrate the presence of true branching in this organism ; but his 

 observations are contrary to those of most other observers, and the reasons he advances 

 for assigning it to the Hcemophilus group are not convuicing. There is some ground for 

 believing (see Dienes and EdsaU 1937) that the organism isolated by Theobald Smith 

 from the pneumonic lungs of calves, and called by him B. actinoides, is closely related 

 to, if not identical with, Streptohacillus moniliformis. Since there is stUl some doubt 

 about this, we shall for the moment describe it in the Actinobacillus group (see p, 389) 

 to which its normal morphological appearance would naturaUy assign it. 



Erikson (1935), who has recently studied a number of new parasitic species of 

 Actinomyces, has suggested a scheme of classification containing both morphological 

 and physiological characteristics. She accepts 0rskov's grouping, but does away 

 with the distinction between his Groups IIA and IIB. She objects to the use of 

 oxygen requirements as a basis of classification on the ground that the distinction 



