and Laboratory Methods. 2035 



Synthetic Media : No reduction of nitrates. 



Bouillon: In one day, at 37°, a slight turbidity, and afterwards a heavy 

 white deposit is formed. 



This species appeared very frequently in all samples examined, but never in 

 very large numbers. In old gelatin and agar cultures, spores appeared at the 

 ends of the bacilli. Two cultures from these heated for 10-15 minutes at a 

 temperature of 85°-90° germinated in one day. The species is very similar to 

 Bacillus No. 18, Conn, but differs in that growth on potato is not spreading, and 

 no spores are found in potato cultures. 



VII. Bacillus No. VII. 



Occurrence : Of variable occurrence in milk examined. 



Ge?ieral Characters : Shape and arrangement — Bacillus occurring singly and 

 in chains. 

 Size — Variable. From 3 to 1^ times as long as broad. 

 Motility — Motile, but not actively so. 

 Spore formation — Observed in old gelatin cultures. 

 Relation to temperature — Grows at room temp., but optimum is 37°. 

 Relation to air — Aerobic and slightly facultative anaerobic. 

 Relation to gelatin — Slow liquefier. 

 Color— White to yellowish. 

 Stain — Stains evenly with aniline dyes. 

 Gelatin : Stick culture — Faint beaded growth along line of puncture. Lique- 

 faction crateriform, a thick, tough, white scum being formed on top. 

 After a few days the liquefaction becomes horizontal with a scum 

 on top and a deposit on the bottom. 

 Plate culture — Surface col; large, flat, round, raised colonies, with 

 a dense white to yellowish nucleus, and a clearer outer granular 

 zone marked by concentric circles. 

 Agar: Streak culture — An opaque porcelain colored, waxy growth, not 



spreading much. 

 Milk : A hard, homogenous, solid, acid curd, with no gas, is formed in two 

 days at 37°. In some cases there is no separation or digestion. In 

 other cases there is very slight digestion. 

 Potato : Extensive growth, dry, elevated, and somewhat reticulated, and 



creamy to yellow in color. 

 Smith Tube : No gas produced in either glucose or lactose. 

 Synthetic Media : No reduction of nitrates. 

 Bouillon: In one day at 37° becomes uniformly turbid, after which a white 



scum is formed on top and a deposit below. 

 This bacillus was quite constantly present for some weeks, but afterwards 

 disappeared. It seems to resemble B. cremoris (18) {B. lactis No. 9, Fliigge), but 

 differs in its effect on milk, so that it would appear to be an allied species. 



VIII. Bacterium No. VIII. 



Occicrrence : Of variable occurrence in milk examined. 



