306 STATE BOARD OF AGRICXJLTUKE. 



II tliin film spreading out over the surface. Tliere is no cliange in the color of this 

 vegetable, but the odor is sour. 



Sui/ar beet. — No visible growth appears on tiie surface, but the JKHiid in tlic bottom 

 of the dish is dense with germ life. 'J'he odor and color are normal. 



Onion. — A slight, whitisli growth apjjcars upon tiie surface of the slices, liut the color 

 of the onion is not changed. 



Carrot. — A dry, white, wrinkled scum forms on the surface, the wrinkles radiating 

 from the center. The growth is heavy and has a tendency to extend over the entire 

 surface of the carrot, while the odor is of a scnir vegetable. 



Turnip. — Growth is abundant in a white, inealy-likc lilm. Color of the turnip 

 is unchanged and the sour odor less pronounced than in other vegetables. 



J{td beet. — There is a very slight lilm spreading over the surface. Beets do not smell 

 unlike ])ickled beets. 



Milk eiiltiire. — At first there is no percei)tible change in the milk other than the 

 gas visible in coming to the surface. As the culture grows older, there is an evident 

 acid formation, .suflicient to produce a partial coagulation of the casein. In litmus 

 milk, the change of the litmus to red indicates the formation of acid. Upon standing 

 for ninety days, the acidity dimini.shes to the neutral point, and the litmus again 

 becomes blue, showing an alkaline reaction. The temperature under which the milk 

 culture was studied was that of the room. 



liiilo! rraetioii. — In Dunham's solution it gives positive reaction in forty-eight 

 hours. 



Growth. — Very rapid between 30 and 38 degrees C. In milk, it easily outstrips the 

 lactic acid germs under ordinary conditions. 



Tempera III re.— Grows readily from 20° to 30° C. From 30° to 38° growth is rapid. 

 Minimum temperature is about 15° C, 0])timum temperature about 37° C, and the 

 inaxinunn temjierature about 41° C, that is, it jnactically ceases to grow at this 

 temperature. Killed at G0° C. for ten minutes. 



Oxyqen requirements. — The influence of oxygen is not decisive. It grows as readily 

 in hydrogen as in the ordinary air conditions; in fact, the growth in hydrogen at 

 times was more abundant than the growth in air. The gas production does not seem 

 to be interfered with in any way under hydrogen conditions. 



Acid production. — Lactic acid is usually produced in small quantities at first, grad- 

 ually increasing in milk cultures until cultures are very old. Although qualitative 

 tests point to tlie formation of acetic acid when grown upon vegetables, yet it cannot 

 be stated definitely that such is the case. 



Alkaliue compounds. — The peculiar change in the reaction of milk after the dura- 

 tion of ninety days seems to point to a nitrogenous decomposition which is scarcely 

 sufficiently marked to yield to chemical analvsis. Yet tliis has its significance in the 

 ripening of cheese where the nitrogenous environment and anaerobic conditions would 

 naturally further nitrogenous fermentation. It is a fact that cheese made with this 

 germ as a starter always lacks in acidity, is insipid to the taste and tinges on the 

 putrid class, none of which characteristics may be attributed to the presence of hydro- 

 gen formed by this germ in milk under ordinary conditions. The odor is that of 

 putrid taint in cheese. For the above reasons. I am inclined to tliink that this 

 micro-organism is capable of acting upon nitrogenous bodies, as in cheese, and pro- 

 ducing products which are not found in its action upon milk under ordinary circum- 

 stances. 



Oas production. — When grown in milk, hydrogen and carbonic acid gas are evolved 

 in proportions of one to five. This, however, is variable, as will be noted in the pre- 

 ceding discussion. 



Odor. — In the common nutrient media there is no perceptible odor. In milk no odor 

 appears until the cultures become so old that it is hardly safe to determine odors. 

 As has been stated, in cheese made with tliis micro-organism as a starter, there is a 

 putrid taint, but of course it would be unsafe to draw the conclusion that it is due to 

 the action of this micro-organism alone. 



Pigment production. — Ordinarily, there is no evidence of pigment, biit when grown 

 on vegetables, in some instances, as the cultures become old, the gi'owth becomes of a 

 dirty brown color. 



Behavior to gelatin. — Liquefaction of the gelatin has been determined in no instance. 



Pathogenesis. — When injected into guinea pigs, either subcutaneously or intra-peri- 

 toneally, death resulted in a short period. One cubic centimeter introduced intra- 

 peritoneally produced death in a .500 grams guinea pig in twenty-four hours. The 

 abdominal organs were covered with a purulent layer consisting of pus cells and bac- 



