37^ Journal of Agricultural Research voi. xin, no. 7 



FURTHER TEST FOR ANAEROBISM 



The organism will not grow in an atmosphere deprived of oxygen. 

 Tests were made by placing agar and botiillon transfers in a specially 

 devised jar from which the oxygen was removed in the following way: 

 40 gm. of pyrogallic acid were dissolved in potassium hydroxid (35 gm. 

 to 350 c. c. of water), and this mixture was placed uncovered in a bottle 

 in the jar with the cultures. The top of the jar was covered; then 

 another cover inserted in, a bed of mercury was placed over the whole. 

 The experiment was v/atched carefully, yet no grov/th could be detected 

 until the cultures were removed at the end of two weeks, when one of 

 the bouillon cultures was found to have developed a few threads of fila- 

 mentous growth extending from the surface into the medium, but no 

 clouding occurred. No growth occurred in, the stab cultures, a trace of 

 growth in one tube not being considered significant. The control cul- 

 tures showed good growth in one day. After removal from the jar 

 growth took place in the bouillon cultures, but there was none in the 

 agar. 



RELATION TO LIGHT 



The organism is not very sensitive to sunlight. Thinly sown agar 

 plates were exposed bottom side up on cracked ice, one side of the plate 

 being covered with black paper. Midday on bright sunny days in early 

 winter was taken for the test. The temperature of the ice bag was 8° 

 to 10° C. A 40-minute exposure did not kill the organism, and in some 

 tests even a few colonies appeared after 50 minutes' exposure; but no 

 colonies appeared on those plates exposed for 60 minutes. 



RELATION TO MOISTURE 



The organism is not killed very readily by drying. Drops of a i -day- 

 old bouillon culture were transferred to sterile cover glasses in a petri 

 dish, and the dish was placed in the dark. The temperature of the room 

 during the days of this test was 25° to 30° C. When kept for two days, 

 and dropped in tubes of bouillon, growth occurred; but no growth 

 occurred in those tubes which received covers on which the organism 

 had been drying for three days. 



VITALITY IN CULTURE MEDIA 



This bacterium lives for more than a year in liquid culture media 

 when cultures are kept in the refrigerator at temperatures of 12° to 

 15° C, and do not evaporate readily. At room temperatures (20° to 

 25°) it lives from two to three months. Milk and litmus milk are 

 the most favorable media for continued growth at these temperatures. 

 In two months the organism is dead in bouillon and on potato cylinders. 



