PRESENT STATUS OF INVESTIGATION OF BEE DISEASES. 49 
BaciILitus A. 
(B. mesentericus?) 
Occurrence.—F ound very frequently on combs, on scrapings from hives, and on 
the bodies of bees, both diseased and healthy. 
Gelatin colonies.—Very young colonies show irregular edges, but very soon 
liquefaction takes place and the colony gives rise to a circular liquefied area, 
covered with a gray membrane, which later turns brown. 
Ager colonies.—Superficial colonies present a very irregular margin consist- 
ing of outgrowths taking place in curves. Deep colonies show a filamentous 
growth having a moss-like appearance. 
Morphology.—In the living condition the bacilli appear clear and often granu- 
lar, arranged singly, in pairs, and in chains. The flagella are distributed over 
the body. The rods measure from 3 to 4 in length, and from 0.9% to 1.2 in 
thickness. 
Motility—The bacilli are only moderately motile. 
Spores.—Spores are formed in the middle of the rod. 
Gram’s stain.—The bacilli take Gram’s stain. 
Oxygen requirements.—Aérobic and facultatively anaérobic. 
Bouillon.—Luxuriant growth in 24 hours, with cloudiness of medium; a gray 
flocculent membrane is present. Later, the membrane sinks and the medium 
clears, leaving a heavy, white, flocculent sediment, with a growth of the organ- 
isms adhering to the glass at the surface of the medium. Reaction alkaline. 
Glucose.—Luxuriant growth takes place in the bulb, with a moderate, floccu- 
lent growth in closed arm. ‘The gradual settling of the organisms causes a 
heavy white sediment to form in the bend of the tube. The reaction is at first 
slightly acid, but subsequently becomes alkaline. No gas is formed. 
Lactose.—Reaction alkaline. 
Saccharose.—Reaction alkaline. 
Levulose.—Reaction acid. 
Maltose.—Reaction acid. 
Mannite.—Reaction alkaline. 
Potato water.—Reaction alkaline. 
Agar slant.—A luxuriant growth takes place on this medium. The growth 
gradually increases to a moist, glistening one, being then friable and of a grayish 
brown color. 
Serum.—A luxuriant, brownish, glistening, friable growth spreads over the 
entire surface. No liquefaction is observed. 
Potato.—An abundant fleshy growth of a brown color spreads over the entire 
surface. The water supports a heavy growth. The potato is slightly discolored. 
Milk.—Precipitation takes place rapidly, followed by a gradual digestion of 
the casein, the medium changing from the top downward to a translucent liquid, 
becoming at last semitransparent and viscid. 
Litmus milk.—Precipitation of the casein takes place usually within 24 hours, 
followed by a gradual peptonization. Reduction of the litmus cecurs rapidly, 
leaving the medium slightly brown; later the blue color will return on exposing 
the milk to the air by shaking. Reaction alkaline. 
Gelatin.—An abundant growth takes place with rapid, infundibuliform lique- 
faction. A heavy, white, friable membrane is formed on the surface of the 
liquefied medium. A flocculent sediment lies at the bottom of the clear liquefied 
portion. p 
Acid agar.—Growth takes place. 
Indol.—None has been observed. 
Nitrate.—Reduction to nitrite is positive. 
30547—No. 70—07 mu 4 
