Dec. 8,1923 
Cutworm Septicemia 
489 
Morphology. —The rods in 24-hour agar cultures are so short that many of them 
resemble cocci (PI. 1, B). Those which appear spherical measure about 0.6 micron 
in diameter, while others which appear ovoid are about 0.75 micron in length and 
about two-thirds as thick. Some of the rods are 1 micron or more in length and from 
0.5 to 0.8 micron in thickness, while in older cultures longer rods and even filaments 
occur. In bouillon cultures the rods average larger, being both longer and thicker 
(fig. 1; PI. 1, A). The shorter rods supplied with flagella possess most often one or 
two of them (fig. 2). Occasionally three or four are present, but rarely more. These 
spring from almost any part of the organism, but usually from near a pole. Spores are 
not produced. 
Motility. —The movements of the bacillus are both progressive and whirling. 
Staining properties. —The rods stain readily with the usual anilin dyes and are 
Gram-negative. 
Agar plate. —The colonies on plain agar form rapidly and have a well defined, 
entire border and an oval, glistening surface. They are bluish by transmitted and 
grayish by reflected light. The colony structure is finely granular and more or less 
uniform. The growth is nonviscid and adheres to the medium. 
Gelatin plate. —Within 24 hours a small area of liquefaction is present about the 
colony. 
Agar slant. —Within a day a moderate, bluish-gray growth occurs which is con¬ 
fined approximately to the surface inoculated. 
Gelatin stab. —In 24 hours at room temperature, a white growth is seen along the 
line of puncture, with beginning liquefaction along the entire needle tract. This is 
more marked near the surface of the medium. In three days the liquefied portion 
is infundibuliform and at the surface has reached the wall of the tube. 
Potato. —Within 24 hours a moderate, gray, moist growth occurs, which increases 
and becomes slightly yellowish. The potato becomes a grayish brown. Gas is formed. 
Bouillon. —Within four hours the medium becomes slightly cloudy and within a 
day turbid. It remains cloudy even in old cultures. A slight ring of growth adheres 
to the wall of the tube at the surface of the medium, a very delicate pellicle may be 
present, and a heavy friable sediment forms. 
Milk. —Within a day a soft coagulum is present which is slowly digested, one- 
fourth being dissolved within a week and three-fourths within a month, leaving a 
yellowish whey. 
Litmus milk.— Slight acidity is formed at first, which changes soon to alkalinity. 
The color is entirely discharged within a week. 
Carbohydrates. —In many instances the presence of a carbohydrate increases the 
luxuriance of the growth. Acid is produced in dextrose, levulose, galactose, man¬ 
nose, saccharose, maltose, glycerin, mannite, xylose, dextrin, and salicin; very little 
is formed in lactose and arabinose; and none in raffinose, inulin, and erythrite. Gas 
is produced in small but visible quantities in glucose, levulose, mannose, saccharose, 
and salicin (Table I), and possibly occasionally in some of the other media. 
Sugar-free bouillon. —Indol is negative. 
Blood agar plates. —Whole rabbit’s blood is not hemolyzed. 
