Oct. 27, 1923 
A Bacterial Stripe Disease of Proso Millet 
155 
There is a distinct odor of decay. When broth cultures have been 
* inclosed in a case or chamber for some days the odor is strong and dis¬ 
agreeable. Only a small quantity of sediment is formed at the bottom 
of the tube which on being shaken appears to be more or less viscid but 
breaks up rather readily to form a part of the clouding. 
Agar slant. —Growth on +15 (P H 6.8) beef-peptone agar is moder¬ 
ate, filiform, slightly raised, shining, smooth, translucent, white, some¬ 
times iridescent, of butyrous consistency to somewhat viscid. There is a 
strong odor of protein decomposition. The medium is unchanged. 
Agar colonies. —On +15 beef-peptone agar colonies grow slowly at 
room temperature, measuring 1 to 1.5 mm. in 48 hours, and 1 to 5 mm. 
in 4 days. Colonies are round, white, slightly iridescent, smooth, shining, 
raised. The margin is entire at first but after 3 to 4 days wedge-shaped 
growths appear (PI. 4, C) around the outer edge which gives an undulate 
margin. Internally, the colonies are finely granular but the wedge- 
shaped growths have fine markings similar to those of the wheat and 
barley organisms. There is a strong odor similar to that of B. coli. The 
center of the colony is denser and quite definitely marked off from the 
rather broad margin. Growth on potato agar is similar. 
Gelatin colonies. —Growth is slow. Surface colonies are circular, 
raised,' with margins entire, and internal structure granular (PI. 4, A). 
Embedded colonies are irregularly lobed (PI. 4, B). Liquefaction is 
saucer-shaped, and takes place slowly at room temperature. In the ice 
box there is no evident liquefaction. The colonies grow very slowly 
and the media dries as fast as any liquefaction takes place. The only 
evidence of liquefaction in the ice box is the fact that surface colonies 
grow in saucer-shaped depressions. In one set of plates the surface 
colonies after 12 days showed cup-shaped depressions in the centers 
of the colonies (PI. 4, D, E). 
Gelatin stabs. —Growth is best at the top with slight filiform growth 
along line of puncture. Liquefaction is crateriform and very slow in the 
ice box. Tubes held in the ice box for a year were entirely liquefied. 
One set of tubes were kept at room temperature. The controls did not 
liquefy, but at the end of two months the inoculated tubes were about 
half liquid. 
Potato cylinders. —Growth is moderate in amount, filiform, flat, 
glistening, smooth, butyrous, light cinnamon-buff to tawny olive (Ridg- 
way), with a penetrating odor of decay. The cylinders are grayed. 
There is moderate diastasic action on starch. 
Temperature relations. —Optimum 33 0 to 34 0 C. Maximum above 
45 0 . Minimum 5.5°. Thermal death-point about 51 0 . 
Cohn's solution. —Growth is slight and nonfluorescent. Precipitate 
stained from a slightly clouded tube showed many long chains. These 
chains do not always appear. 
Uschinsky's solution. —Clouding is moderate to heavy and non¬ 
fluorescent. A thin pellicle forms at first which breaks up on shaking. 
After a week or two the pellicle hangs in long strands down through the 
liquid from a small surface disk. There were no long chains on stained 
slides. 
Fermi's solution. —The clouding is heavier than in either Cohn's or 
Uschinsky’s solution. A thin pellicle forms which is not continuous but 
like lacework; nonfluorescent. Pellicle and precipitate break up on 
shaking. There are no chains on stained slides. 
