52 COD AND OTHEK SALT EISH FOB THE MARKET. 



BACILLUS. 



The bacillus is a rod, thicker at one end than the other, due to the 

 formation of a spore. The bacilli vary in diameter from 0.9 to 1.3 /u 

 and in length from 5 to 10 /A on bread, while in sea-salt gelatin the 

 length is 5.7 p and over. In beef gelatin and agar the length varies 

 between that on bread and that on sea-salt gelatin. They are motile 

 in young cultures on nearly all media used, and produce liquefaction 

 in gelatin. They are colorless on all media except bread, which as- 

 sumes a pink tint. They are aerobic, the growth tapering gradually 

 from the surface in stab cultures, and in plates in which parallel lines 

 of growth were made, parts being covered with sterilized cover 

 glasses, no growth occurred under the covers ; in gelatin plates there 

 was no liquefaction under the covers. No viscosity is found in the 

 cultures. The organism stains readily, the same stains being used as 

 on the coccus. 



GROWTH IN VARIOUS MEDIA. 



Beef bouillon. The organism causes turbidity in this medium, a 

 thin film forms in a few days, and in a week a fairly heavy sediment 

 is developed. 



Milk. An oily ring is developed at the surface, but no perceptible 

 change occurs in the milk. 



Gelatin. The bacillus liquefies the gelatin slowly, in five days a 

 funnel-shaped depression being formed. When the gelatin is entirely 

 liquefied, it is clear, with a medium amount of grayish sediment. 

 Many spores are formed in this medium. The reaction of the lique- 

 fied gelatin is +1. 



Agar. In this medium a thin oily, grayish growth is formed on 

 the surface, with a white rim at the edge that appears thicker than 

 the older central part, and a thin uniform development along the 

 puncture. No development took place in agar plus 5 and 10 per cent 

 of salt, respectively. 



Sea-salt gelatin. The organism grows very slowly in this medium, 

 liquefying it much more slowly than the beef gelatin, small zooglcea 

 masses being formed. When entirely liquefied, a very small amount 

 of sediment is present, and the gelatin is perfectly clear. The organ- 

 ism attains a greater length in this medium than in any other tested. 



Bread paste. On the paste a thick, creamy layer is formed over the 

 entire surface. The organism penetrates the paste; in eight days 

 that near the surface has a pink tint, and in two months the paste to a 

 distance of three-quarters of an inch is a decided pink with a some- 

 what watery appearance. As the culture ages, the creamy color 

 darkens, becoming brownish. 



