June 25, 1909] 



SCIENCE 



1011 



either on the top or on the bottom of the agar 

 surfaces. In glucose agar stab tube no gas is 

 formed and the stab growth is smooth, delicate 

 and whitish. On potato no growth has been ob- 

 tained, but on Heinemann's synthetic potato 

 medium a so-called " invisible " growth occurs. 

 Broth is moderately clouded and occasionally a 

 delicate surface film is formed. In gelatin the 

 stab extends nearly all the way down the needle- 

 track in a smooth, even manner and of a grayish 

 color; the surface growth is scant, delicate and 

 pearly gray; a saucer-shaped zone of liquefaction 

 makes its appearance upon the surface about the 

 third to the tenth day, and progressively extends 

 outwards and downwards until the whole of the 

 gelatin is liquefied. Occasionally where liquefac- 

 tion has been delayed feathery outgrowths from 

 the stab have been observed. In litmus milk 

 growth does not readily occur imless the medium 

 has been heavily seeded, then a slow-appearing 

 alkaline reaction makes itself noticeable about the 

 third day at the surface of the medium, which 

 later on extends throughout the tube, eventually 

 rendering the milk semi-translucent; no clotting 

 or proteolytic changes have ever been seen. On 

 Jordan's asparagin medium a well-marked surface 

 film growth takes place with an ultimate slight 

 clouding of the whole medium. 

 'Note on a Lactic Acid Forming Bacillus Closely 

 Resemhling B. bulgarious Isolated from Corn- 

 meal: P. G. Heinemann and Mar y Heffekan, 

 University of Chicago, Chicago, 111. 

 During an investigation of yeasts for the prepa- 

 ration of so-called salt-rising bread a bacillus was 

 isolated which, as far as the examination has pro- 

 ceeded, agrees in morphology, staining properties, 

 cultural characteristics and the ability to produce 

 large amounts of lactic acid from milk with the 

 characteristics of B. iulgaricus, the organism 

 which has recently received considerable attention 

 and has been recommended by Metchnikoff for the 

 preparation of sour milk. A stain from the mix- 

 ture of cornmeal, milk, sodium bicarbonate and 

 salt showed a large number of bacilli with the 

 characteristic granular staining of Metchnikoff's 

 bacillus. After cultivation in milk the bacilli 

 stained uniformly. When granules appear the 

 picture recalls somewhat the appearance of small 

 spores and seems to agree with Kuntze's descrip- 

 tion of his " Kornchen " bacillus. Attempts to 

 obtain these bacilli in pure culture by plating on 

 the ordinary laboratory media failed utterly, but 

 they were readily isolated if cultivated in milk 

 at 37° C. or if plated on milk-agar. The colonies 



after a few days have peculiar root-like ramifica- 

 tions on milk-agar and may be mistaken for small 

 colonies of B. siibtilis. In pure culture the milk 

 is coagulated slowly, rarely in less than two or 

 three days. The coagulum is soft and creamy, 

 without the separation of whey, and unlike the 

 more solid coagulum formed by Streptococcus lac- 

 ticus. The amount of lactic acid produced in 

 milk is much higher than the amount produced 

 by 8. lacticus. After fourteen days 1.65 per cent, 

 acid was determined. By addition of glucose or 

 lactose to ordinary agar a moderate growth ap- 

 peared after two or three days. If this bacillus 

 is sowed into sterile milk with a culture of 8. 

 lacticus, acid is formed more rapidly than by 

 either of the two organisms alone and the coagula- 

 tion of the casein is also more rapid. 



Salt-rising bread is started by mixing cornmeal, 

 milk, sodium bicarbonate and salt. It seems that 

 milk is a necessary part, without which probably 

 the bacillus is unable to grow and form the neces- 

 sary lactic acid for liberating carbon dioxide from 

 sodium bicarbonate. By inoculation of sterilized 

 milk with cornmeal it was ascertained that the 

 bacillus originated from the cornmeal and not 

 from the milk. It is, therefore, quite possible 

 tnat this bacillus is widely distributed and an 

 investigation is now under way to determine the 

 distribution. We are attempting to isolate this 

 bacillus from a large variety of sources, prin- 

 cipally flours, dry fodder, silage, feces of man 

 and domestic animals, sourkrout and other sim- 

 ilar substances. The study has extended over a 

 period of a few weeks and we hope to be able to 

 make a more complete report in the near future. 



The Oas Production of B. coli: Feedebick Gr. 



Keyes, Brown University, Providence, R. I. 



All previous work on gas production has been 

 of little value because of imperfect methods of 

 collecting and analyzing the gases produced. 



The ordinary fermentation tube does not give 

 the exact amounts of gas produced because of the 

 solution of the gases in the medium and its dif- 

 fusion therefrom. 



The methods ordinarily used by the bacteriolo- 

 gist for analyzing the gases produced are imper- 

 fect because they give merely the CO™ content and 

 tell little about the other gases which may be 

 present. Also, standard media, even at best, are 

 sufficiently variable to influence materially the 

 amount and composition of the gases produced. 



Therefore the writer set about to devise an 

 apparatus which would enable him to collect and 



