BACILLUS SUBTILIS. Ehrenberg. 



HAY BACILLUS. 



Origin. In air, water, soil, feces, putrid fluids, and 

 in infusions of hay. 



Form. Lame, rather narrow rods, about 3 times as 

 long as wide, and with rounded ends. Forms threads. 



Motility. Actively motile. Has a flagellum at 

 each end. 



Sporulation. Forms large, oval spores at or near 

 the middle, without enlargement. Are highly resistant 

 and can be readily double stained. 



Anilin Dyes. Stain readily. 



Growth. Very rapid. At 21 0. the division of a 

 cell has been observed to take place in 1 hours, and at 

 35 in 20 minutes. 



Gelatin Plates. The surface colonies liquefy gelatin rapidly and exten- 

 sively and present a characteristic appearance. The central portion appears 

 as a grayish yellow, irregular mass, which enclose examination can be seen 

 to be made up of moving cells. The border of the colony is quite character- 

 istic. It consists of a dense zone of bacilli and threads, radially arranged, so 

 that the ends project outward, thus presenting a peculiar appearance the so- 

 called "ray crown." . 



Stick Cultures. Very rapid liquefaction takes place along the entire line 

 of inoculation. White flocculent masses accumulate at the bottom while the 

 liquid above, at first turbid, becomes clear. On the surface a dense white 

 scum or zoogloea usually forms. 



Streak Cultures. On ayur, forms a grayish white, thick, folded scum. 

 On potatoes, develops excellently, and forms a moist, thick, yellowish-white 

 covering, which at first is velvety in appearance but later becomes dry and 

 granular, and contains spores as well as involution forms. On blood serum, 

 forms also a folded scum and liquefies. 



Oxygen requirements. Is aerobic. 



Temperature. Grows from 10 to 45. Optimum 

 about 30C. 



Behavior to Gelatin. Liquefies rapidly and exten- 

 sively. 



Pathogenesis. Has no pathogenic power. Large 

 numbers of spores injected into the blood soon disappear 

 and are taken up by the liver and spleen. They may be 

 stored up in these organs for 60 to 70 days and yet pre- 

 serve their vitality (Wyssokowitsch). 



