CLASSIFICATION OF DAIRY BACTERIA. 137 
Gelatine stab.—A deep, dry pit is first formed which, after several days, shows 
liquefaction. 
Agar streak.—A luxuriant, moist, yellow to white growth. 
Bouillon.—A sediment, turbidity, and pellicle. The liquid later becomes 
clear. 
Milk.—Becomes alkaline and curdles. It subsequently digests into a clear 
liquid, with a tenacious scum. 
Potato,—Luxuriant, dry, rough, wrinkled, with a brilliant yellow color. 
Grows at both 20° and 37°. Aerobic. 
Bact. lactis arborescens II, An arborescent spore-bearing Bacterium. This 
organism, originally found in 1896, has appeared once or twice subsequently, 
although the later organisms differed slightly from the original. One-culture, 
sent by Weigmann, differed in points inclosed in brackets. 
Morphology.—Rods with square ends. Size, 2u-4ux Iu-1.8m¢, forming long 
chains. Spores are produced but no capsules. Gram stain negative. 
Gelatine colony.—A very peculiar felted mass of fibers extending through the 
gelatine, and a ground glass-like felted surface, on a liquefying disk. The 
appearance is variable, but the fibers are characteristic. [Myceloid.] 
Gelatine stab.—An arborescent needle growth, liquefying slowly, infundibuli- 
form, with a folded, ground glass-like scum. 
Agar streak.—Widely spreading, filamentous and somewhat cotton-like on 
the surface and extending into the agar; luxuriant, wrinkled, dull. [Cretaceous. ] 
Fermentation tubes.—[Dextrose and saccharose acid, lactose not acid, no gas, 
closed arm growth in lactose and saccharose. ] 
Bouillon.—A flaky turbidity, a sediment, and a ground glass-like scum. 
Milk.—Alkaline, curdled and digested. After digestion it may be amber- 
colored or colorless. One culture showed a ground glass-like scum. 
Potato.—A luxuriant growth, with a white cotton-like surface, extending below 
into the potato. 
Grows at both 20° and 37°. Aerobic. 
In the specimens found later and regarded as the same as the above the 
arborescent needle growth was not always found, and the scum on the milk was 
lacking. 
Bact. lactis filiformis, formerly described, is very similar to the last and 
may be the same. It has not been found since the original description. It 
differs only in the following points: No arborescent growth in gelatine. The 
ground glass-like appearance is lacking. The agar streak shows a dry, white, 
lobate growth. Bouillon shows a scum of tangled fibers, and on potato it forms 
a thick, slimy growth, yellowish, covering the whole surface of the potato. 
Bact. lactis truncatum, A Bacterium with proteus or curled colonies. De- 
scribed by us in a previous report and named by Chester. The following is a 
description of a culture studied more recently: 
Morphology.—Size, 1.24-2.54x .8u-1, forming long chains of square-ended 
rods. Spores are produced but no capsules. 
Gelatine colony.—An opaque colony, 3{ inch in diameter in two days; curled, 
i. ¢., made of twisted threads. In some cases the colony is proteus-like, with 
threads in parallel rows. 
