EXPERIMENT STATION BULLETINS. 459 



"When transplanted to gelatin the colonies began to sink into the gelatin, 

 in thirty-six hours leaving saucer-like depressions, and a floating film formed 

 on the surface of the liquefied gelatin. The growth in the bouillon was 

 rapid, producing very little cloudiness, a pellicle forming on the top which 

 grew fast to the wall of the test tube. The bacilli were actively motile, ex- 

 hibiting their motility in twisted, writhing masses. 



"The cultures all had the odor of H2S, and in a few days the sulfur would be 

 strong enough to bleach out the blue color made with the blue pencil on the 

 glass petri dishes and test tubes. I inoculated several cans of peas which 

 had been sterihzed, with some of these organisms, and in two or three days 

 the cans had the same appearance and taste as the original two cans. I 

 tested other cans by inoculating them with spores from the organism and 

 processing at 240°F for twenty-five minutes. Of the twelve cans so treated 

 only two were sterilized. Ten of these cans had a natural appearance, 

 showed no sign of swelling, but turned sour in five days in the incubator. 

 The spores of the organism are quite large, are situated near the middle, or 

 perhaps a little nearer the end of the cell. The cell seems to split open at 

 the side, setting the spore free." 



Method Employed for Bacteriological Study of Flat Sour Peas 



In order to simulate as closely as possible the composition of canned 

 peas, a pea agar was prepared in the following manner: 



1,000 gms. peas (canned). 

 4,000 c. c. water. 

 60 gms. agar. 



The agar was boiled in water until dissolved. The water which had evap- 

 orated was replaced. The canned peas were mashed and added with their 

 juice to the agar solution, and the medium was autoclaved for thirty minutes 

 at fifteen pounds pressure. After autoclaving, the medium was cooled 

 slowly. This allowed the broken skins and pulp to sink to the bottom, and 

 when the agar had solidified the sediment was cut away and discarded. 

 The remaining clear agar was melted, colored with litmus, and autoclaved. 



The starch agar employed in this experiment was made according to the 

 following formula: 



Agar, 10 gms. 



Diabasic potassium phosphate, 0.2 gms. 



Magnesium sulphate, 0.2 gms. 



Potassium carbonate, 0.4 gms. 



Calcium chloride, 0.02 gms. 



Ferric sulphate, 0.02 gms. 



Sodiiim chloride, 0.02 gms. 



Tap water, 500 c. c. 



Starch solution, 500 c. c. 



The mineral salts and agar were boiled together in tap water, the water 

 which was lost in evaporation being replaced with distilled water. 500 c. c. 

 of starch solution was added. The starch solution was made as follows: 

 To 10 gms. of potato starch suspended in a little cold water 500 c. c. of boiling 

 water was added. The solution was concentrated to 500 c. c. All other 

 media used in this experiment were prepared according to the standard 

 formulae. 



