Bacillus Megaterium, De Bary. 



Origin. — Originally found on boiled cabbage leaves, 

 but may be present on other vegetable matter; also found 

 in the air and in soil. 



Form. — Large cylindrical rods, with granular contents, 

 three to six times as long as broad, with rounded ends. 

 They are usually slightly bent, are in pairs, and may form 

 threads. Involution forms are very common. Capsulated 

 cells are especially found in the slimy growths. 



Moxh-iTY. — Slow, creeping motion. 6-8 lateral flagella, 



Sporulation. — Itforms median spores. 



Anilin dyes. — Stain readily, though irregularities due 

 to granular protoplasm may be seen. 



Growth. — Rapid. 



Gelatin plates. — Colonies are at first irregular, small, yellowish 

 masses, but subsequently show marked radiating or branching forms, 

 which soon liquefy the gelatin. Kidney-shaped colonies may be met 

 with. 



Stab cultv/re. — Rapid growth and liquefaction along the line of 

 inoculation. May show threads of bacteria penetrating outward into 

 the solid gelatin. Eventually, the gelatin is wholly liquefied and a 

 flocculent mass accumulates on the bottom; the supernatant liquid 

 clears up without formation of scum on top. 



Streak cultv/re. — On agar, it forms a dull white or grayish cover- 

 ing. On potato, it grows rapidly as a thick, slimy, grayish white 

 mass, which is rich in spores and involution forms. 



Oxygen requirements. — It is aerobic. 



Temperature. — The optimum is at about 20°. It may, 



however, grow in the incubator. 



Behavior to gelatin. — It liquefies rather slowly. 



Pathogenesis. — No effect observed. 



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