. Bacteria in relation to plant diseases. Bacteriology; Plant diseases. Bacillus caucasicus is described as follows: On ordinary gelatin plates it does not grow at all. Only once, as already stated, did von Freudenreich obtain it on a gelatin plate exposed to anaerobic conditions according to Miquel's method. Other times, using the same method, he did not obtain it. Also on milk-sugar gelatin plates he never observed it. Having once obtained it, it grows in stab- cultures even in ordinary gelatin but then first after a long time. On milk-sugar gelatin plates he often had no growths; at other t
. Bacteria in relation to plant diseases. Bacteriology; Plant diseases. Bacillus caucasicus is described as follows: On ordinary gelatin plates it does not grow at all. Only once, as already stated, did von Freudenreich obtain it on a gelatin plate exposed to anaerobic conditions according to Miquel's method. Other times, using the same method, he did not obtain it. Also on milk-sugar gelatin plates he never observed it. Having once obtained it, it grows in stab- cultures even in ordinary gelatin but then first after a long time. On milk-sugar gelatin plates he often had no growths; at other times microscopic colonies. On the surface of milk agar plates, on the contrary, he often obtained colonies. Upon this it produces small, flat, grayish colonies which appear circular to the naked eye. With a weak magnification they are seen to have irregular contours and are not uniformly circular; they also appear whitish and granular. This granulation is produced he states, by the irregular arrangement of the bacilli, plain to be seen on the edge, out of which the bacillary forms project. In ordinary nutrient bouiUon he could not obtain any growth, not even at 35° C. In milk-sugar bouillon there was a slow growth at 22° C.ânothing to be seen for the first 3 days, but at 35° C. the growth is faster. The reaction was acid. It produces no coagulation in milk although the reaction becomes somewhat acid. The taste of such milk was slightly acid and astringent similar to that produced by the smaller streptococcus when grown in milk. There was a moderate gas formation. There was no growth on potato. In milk-sugar bouillon it appears ordinarily as a straight bacillus with rounded end, often with a shining point at each end. This appearance corre- sponds well, he says, to the phenomenon interpreted as spores by Kern. Their slight resistance to heat, however, shows that they are not spores; also when exposed to staining media the bacillus stains in toto which would not be the
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