GENERAL SYSTEMATIC BACTERIOLOGY 387 



Winslow et al. (Committee Soc. Am. Bact. 1917, p. 554) have used 

 the definition: 



Slender rods which are stained with difficulty, but when once stained are 

 acid-fast. Cells sometimes show swollen, clavate or cuneate forms, and occasion- 

 ally even branched filaments. Non-motile, Gram-positive. No endospores. 

 Growth on media slow. Aerobic. Several species pathogenic to animals. 



The type species is Mycobacterium tuberculosis (Koch) Lehmann and 

 Neumann. 



Buchanan (1918, p. 55) gave the following definition and discussion. 



Slender rods which stain with difficulty, but when once stained, are acid-fast. 

 Clubbed, swollen, clavate or cuneate cells occur, even filaments with branches. 

 Non-motile. Without spores. Gram-positive. 



The type species is Mycobacterium tuberculosis (Koch) Lehmann and 

 Neumann. 



Vuillemin (1913, p. 527) contends that Coccothrix resembles too closely Cocco- 

 trichum Wallroth. It does not seem that the resemblance is close enough ever to 

 cause confusion, and the genus name Coccothrix is apparently valid. The Com- 

 mittee on Classification of the Society of American Bacteriologists, however, has 

 recommended the use of the generic name Mycobacterium as better known and less 

 likely to result in confusion. 



Castellani and Chahners (1919, p. 962) indicate as the type species 

 Mycobacterium leprae (Hausen 1874), and include the diphtheria and 

 glanders types (Corynehacterium) in the genus. 



Bergey et al. (1923, p. 372) follow the Committee, and include the 

 genus as the first in the family Mycohacteriaceae. 



The validity of Mycobacterium as a valid generic name is menaced 

 apparently only by the older Coccothrix Lutz, q.v. Perhaps inasmuch 

 as the latter name has apparently never been used, it may be passed 

 by in the interest of stability. 



Mycococcaceae. A family of bacteria proposed by Hansgirg (1888, 

 p. 266) as the only family of his order Sphaerobacteria. Two sub- 

 families are included, Cystococcaceae and Eucoccaceae. 



Mycoderma. A generic name used by Persoon (1822, p. 96) with 

 the species Mycoderma ollare, M. mesentericum, etc., the latter for 

 the film which forms on beer or wine which is exposed to the air. The 

 individual organisms which compose this scum were not studied. 

 We know that this scum may be of yeasts or of bacteria, frequently 

 a mixture of the two. It is not surprising therefore in the subsequent 

 Uterature to find authors diverging in the use of the term Mycoderma, 

 one group regarding it as a genus of yeasts, the other as a genus of 

 bacteria. 



