200 COMMITTEE REPORT 



Genus 4. Pfeifferella Buchanan 1918b, p. 54 



Non-motile rods, slender, Gram-negative, staining poorly, 

 sometimes forming threads and showing a tendency toward 

 branching. Gelatin may be slowly liquefied. Do not ferment 

 carbohydrates. Growth on potato characteristically honey-like. 



Type species, Pfeifferella mallei (Loeffler 1886) Buchanan (the 

 glanders bacillus) 



The real lines of demarcation between the genera Actinobacil- 

 lus, Erysipelothrix, Fusiformis and Pfeifferella and their relations 

 to Actinomyces on the one hand and to Mycobacterium on the 

 other seem very obscure and the above arrangement can be con- 

 sidered as only tentative. 



E. ORDER EUBACTERIALES Buchanan 1917b, p. 162 



The order Eubacteriales includes the forms usually termed the 

 true bacteria, that is, those forms which are considered least dif- 

 ferentiated and least specialized. The cell metabolism is not 

 primarily bound up with hydrogen sulphide or other sulphur com- 

 pounds, the cells in consequence containing neither sulphur gran- 

 ules nor bacterio-purpurin. The cells apparently do not possess 

 a well-organized or well-differentiated nucleus. These organisms 

 are usually minute and spherical, rod-shaped or spiral, in most 

 genera not producing true filaments; and rarely branching. The 

 cells may occur singly, in chains or other groupings. They may be 

 motile by means of flagella, or non-motile; but are never notably 

 flexuous. Cell multiplication occurs always by transverse, never by 

 longitudinal fission. Some genera produce endospores, particularly 

 the rod-shaped types. Conidia not observed. Chlorophyll is 

 absent, though the cells may be pigmented. The cells may be 

 united into gelatinous masses, but never form motile pseudo- 

 plasmodia nor develop a highly specialized cyst-producing fruit- 

 ing stage, such as is characteristic of the Mkjxobacteriales. 



Family I. Nitrobacteriaceae Buchanan, 1917c, p. 349 



Organisms usually rod-shaped (sometimes nearly spherical in 

 Nitrosomonas and possibly in Azotobacter.) Cells motile or non- 

 motile. Branched involution forms in Rhizobium and Aceto- 



