42 
North Carolina Agricultural Experiment Station 
of carbohydrate. B. carotovorus will, within the first 24-hour period, have de¬ 
veloped a pH concentration from the fermentation of dextrose as great as that 
by any of the other species within 3 to 5 days. All, however, appear to he slow 
acting in contrast with animal pathogenes. B. glycineum ferments both dex¬ 
trose and saccharose with considerable vigor, but not lactose and glycerine. 
With the latter two, there is a reversal of reaction even in a concentration of 
2 per cent. B. campestre does not attack the sugars as evidenced by no in¬ 
crease in pH concentration in any of the cultures. 
Mechanical agitation is decidedly beneficial to the growth of B. glycineum, 
probably due to aeration, the removal of by-products and renewal of food sub¬ 
stances, as lias previously been pointed out. With agitated cultures in 1 per 
cent dextrose the characteristic final pH concentration is attained, whereas 
with undisturbed cultures, there is a reversal of reaction. 
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