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proved that they were not parasitized, and had not been injured. Pure 
cultures on solid media were isolated from the germs found in the 
liquid contents of the pupal skins. One of these germs proved to be 
the cabbage- worm micrococcus. In most portions of the South the dis- 
ease affects only a small percentage of the larvae, and as it is usually 
fully developed only in the pupal form, the contagion among cabbage- 
worms is reduced to a minimum. 
A DISEASE OF PLUSIA BRASSICJE. 
The first symptoms begin to appear about the region of the two white 
lateral patches just below the median line and over the first pair of pro-, 
legs. The patches look like whitish, cheese-like fatty bodies under the 
skin. From these the pale cream color of the body begins and spreads, 
the skin gradually becoming entirely of a lemon-yellow color. The pos- 
terior portion of the body shows these symptoms first, the anterior por- 
tion remaining quite natural in color until about the time of death. No 
fluids appear to issue from the mouth or vent during the course of the 
disease. When well affected by the progress of the disease, the larva 
ceases feeding, dying soon afterward. The entire body deliquesces very 
rapidly after death, producing a blackish, semifluid mass suspended 
in a bag of grayish skin, which finally bursts and allows its contents to 
escape. 
September 4, some living Plusia larvae were found on a cabbage leaf 
near a dead Plusia larva, which was already black and entirely de- 
liquesced. 
Two Plusia larvae and two of Pieris from the same plant were placed 
together in a collecting box, and later placed in the same breeding cage 
to rear. By September 7 the Plusia larvae had died and deliquesced. 
The Pieris larvae had certainly come in contact with the sick Plusia 
while crawling about and feeding upon the same cabbage leaves, and 
had thus been thoroughly exposed to infection. Both larvae, however, 
completed their transformations, and the butterflies showed no unfa- 
vorable symptoms. This experiment was repeated with a greater 
number of larvae of each species with exactly the same results, 
From this it becomes evident that the Plusia disease could not be 
very contagious so far as Pieris rapce was concerned; at the same 
time the disease acts very decidedly and rapidly among Plusia larva3. 
They often begin turning pale cream -colored, then yellowish, dying, 
and the body deliquescing, all within thirty to forty hours. This 
applies to nearly grown larvae, Those less than half grown succumb 
in half that time, 
In the usual manner pure cultures were obtained from the dead and 
deliquescing larvae, Three distinct germs, two of which were found 
almost constantly in the several specimens from which cultures were 
piade, were isolated by the usual process. On agar-agar one of these 
germs produces, at the beginning, numerous small, white roundish 
