Microbiology. — ''On Bacillus poh/myxa"). By Prof. M. W. 

 Beijerinck and L. E. den Dooren de Jong. 



(Communicated at the meeting of September 30, 1922). 



If the species-conception is taken in a not too limited sense, the 

 closely related, but not identic forms mentioned in Note 1, may be 

 said to comprise the only known aerobic spore-forming bacterinm- 

 species, which causes fermentation in a sugar-containing medium. 

 We call it Bacillus polymy.ia. 



It is rather generally spread in fertile soils; its properties are 

 very characteristic and give rise to interesting experiments. The 

 production of aceton first observed by Schardinger, has in the later 

 years drawn attention on this microbe, but the quantity formed is 

 small and from malt or potatoes it does not amount to i 7o of the 

 weight. But the conditions for its formation are not yet well-known 

 and might [)erhaps be greatly improved as to the quantity. Alcohol 

 is also generated and to a somewhat greater amount than aceton. 

 Besides, a little acetic- and formic acid seem to be produced. Par- 

 ticularly the secretion of the enzyme pectinase and of much slime 

 by the chief variety is of interest. 



^) The literature of this Bacterium and its nearest relations is to be found under : 

 Clostridium polymyxa Prazmowski, Granulohacter polymyxa Beijerinck, Bacillus 

 macerans Schardinger and Bacillus asterosiiorus A. Meyer. — A. Prazmowski, Ent- 

 wickelung und Fermentwirkung einiger Bacteriën. Dissert. Leipzig 1880, p. 37. — 

 Th. Gruber, Identifizierung von Clostridium Polymyxa Prazmowski, Gentralbl. f. 

 Bakteriol. 2te Abt. Bd. 14, 1905, pag. 353. — F. Schardinger, Bacillus macerans, 

 Acetonbildender Rottebacillus, Gentralbl. f. Bakt. 2te Abt. Bd. 14, 1905, pag. 772. 

 Zur Biochemie von B. macerans. Gentralbl. f. Bakt. 2te Abt. Bd. 19, 1907, p. 161. 

 Kristallisierte Polysaccharide aus Starke durch Mikrobien. Gentralbl. f. Bakter. 2te 

 Abt. Bd. 22, 1909, p. 98 and Bd. 29, 1911, p. 189. — A. Meijer und G. 

 Bredemann, Variation und Stickstoffbindung durch Bacillus asierosporus. Gentralbl. 

 f. Bakteriol. 2te Abt. Bd. 22, 1909, p. 44. 



The name asterosporus is derived from 9 or 10 rims on the exosporium of 

 the oblong spores, which make the transversal section star-like. By abundant 

 feeding, as on wort-gelatin, many rodlets change into narrow Clostridia con- 

 taining somewhat granulose, colored blue by jodine; so the species may also be 

 called Granulohacter polymyxa. 



18* 



