CLASSIFICATION OF DAIRY BACTERIA. 147 
Potato,—Yellowish-white, slimy, luxuriant. The potato becomes light-blue 
and, later, amber-colored. 
Grows at both 20° and 37°. Aerobic. 
Bact, lactis brevis nr. >. A white liquefier. This has been found several 
times in milk and cheese here and elsewhere. It seems to be identical with one 
sent by Freudenreich and is apparently a widely distributed species. 
" Morphology.—Size, .7u-.9u x .54-.64. No chains, no spores. Gram stain 
irregular; no capsule. ‘ 
Gelatine colony.—A round, thin colony, lobed, whitish. It may show acidity 
in tmus gelatine, and it slowly liquefies. 
Gelatine stab.— Begins to liquefy in from one to two days, and may be com- 
pletely liquefied in from three to twelve days. Stratiform. 
Agar streak.—Fairly luxuriant, smooth, white, not characteristic. 
Fermentation tubes.—All thrée sugars are acid, and there is usually growth 
in the closed arm, but no gas. . 
. Bouillon.—A sediment, but no turbidity, and no pellicle. 
Milk.—Rendered acid and curdled, and later, is partly digested. 
Potato.—Barely visible; thin and white. ‘ 
Grows at 20° and 37°. Facultative anaerobic. 
Found many times, the numerous varieties showing some differences. The 
Freudenreich organism is longer, Iu in length. It makes milk acid and bitter. 
This is apparently A/ilch. Bacterium LI. of Koning (Milchw. Zent. II., p. 317, 
1906). 
Variety A.—This organism, sent by Harding, differs in the following points: 
Size, 2-34x 1.2. Liquefaction of gelatine tube never complete. A pellicle in 
bouillon. Rather more luxuriant on potato. . : 
Bact. lactis fluorescens u. >». A fluorescent Bacterium, This organism, 
being non-motile, seems to be different from the common fluorescent form. We 
have found it but once, in New York city milk. It may be only a non-motile 
variety of B. fluorescens, but we have been unable to detect any motility in our 
cultures. 
Morphology.—Size, I.4u-2.5m xX u-.gp. No chains, no spores, no Gram 
stain and no capsule. 
Gelatine colony.—A slow liquefier, forming a peculiar lace-like colony in a 
pit, with a dense centre. : 
Gelatine stab.—A needle growth, stratiform; liquefaction beginning in one 
day. 
Agar streak.—Filiform, capitate, smooth, translucent, white, luxuriant, with 
a green fluorescence. , 
Fermentation tubes,—Dextrose and saccharose are rendered acid; lactose is 
not; no closed arm growth; no gas. 
Bouillon.—A sediment, turbidity and a pellicle. 
