416 
Journal of Agricultural Research 
Vol. VIII, No. ii 
RECOVERY OF THE ORGANISMS INOCULATED 
In order to determine the presence of the organisms in the inoculated 
colonies, cultures of the young brood were made at frequent intervals. 
This was done by gently removing the larvae from the cells and first wash¬ 
ing in five or six changes of sterile water for the purpose of removing the 
organisms present in the food surrounding the grubs as they lie in the 
cells. After this the larvae were crushed on a sterile microscope slide, and 
a loop of the crushed contents was plated out on an agar plate. By the 
estimation of the number of organisms on the agar plate after 24 hours* 
Fig. 5 .—Bacillus larvae; Smear direct from a diseased larva. X 1,480/ Note tlie small size of the spores 
as compared with those of B. alvei , the lack of any vestige of rod, and the lack of any tendency of the 
spores tc occur in rows. 
incubation, a fair idea is obtained of the number of organisms ingested. 
Of the 34 equivalent colonies inoculated, the organisms were in every 
instance recovered in abundance by culturing the larvae. A loop of the 
crushed larvae, when inoculated onto agar plates, often yielded colonies 
too numerous to count. The organisms were recovered in large num¬ 
bers as early as the next day after the first inoculation. No exhaustive 
study was made fo determine the length of time after the last inoculation 
that the organisms could be recovered, though in several instances they 
were cultured from the larvae as late as eight months after; but the 
organisms were not in sufficient numbers to warrant the conclusion that 
their presence was due to the previous experimental inoculations. Nor- 
