488 
Journal of Agricultural Research 
Vol. XXVI, Na jo 
Since cutworms are of great economic importance, naturally a disease 
of them is of special interest. Cutworm septicemia, moreover, belongs 
to the large and important group of diseases of which the coccobacillus 
infection in grasshoppers and a number of other diseases of insects already 
described are members. While there is much yet to be learned about 
cutworm septicemia, the facts already determined and contained in the 
present paper are sufficient to make possible answers to many of the 
questions likely to be asked regarding the disorder. 
EXCITING CAUSE 
The technique that was used in the study of homworm septicemia is 
very similar to that which has been employed in the work on this cut¬ 
worm infection. Both the puncture and the feeding method were em¬ 
ployed in the inoculations. Before making the puncture no attempt 
need be made to sterilize the field of operation. Check larvae punctured 
with a sterile needle, with one dipped into the blood of another healthy 
worm, or with one contaminated with unsterilized tap water suffer no 
infection or other particular inconvenience therefrom. 
The blood of larvae recently sick or dead of the disease is found to 
contain an actively motile bacillus in large numbers and in pure or 
practically pure cultures. Cutworms inoculated by puncture with a 
pure culture of the bacillus become infected, a pronounced septicemia 
results, and a mortality of about ioo per cent occurs. Cultures made 
from fecal and oral discharges from sick larvae which had been inoculated 
by puncture contain the same bacillus that is present in the blood and 
in even greater numbers. The bacillus does pass, therefore, from the 
blood to the lumen of the alimentary tract, but its portal of escape is 
yet to be determined. Within the alimentary canal of the infected 
larva the bacillus apparently multiplies rapidly. 
So far cutworms inoculated by feeding the bacillus have not shown 
symptoms of cutworm septicemia nor have they died from infection. 
On the other hand septicemia and death have followed the feeding of 
this germ to silkworms. If infection in cutworms can take place, as 
seems probable, through the ingestion of food contaminated with the 
bacillus, the portal of entry of the organism from the alimentary tract to 
the blood is yet to be discovered. 
The presence of a true septicemia is shown also in microtome sections 
of sick larvae infected by puncture, the organisms being found in all the 
blood spaces. The sections, furthermore, show the bacilli within the 
stomach, many not infrequently occupying a position near the epi¬ 
thelium of the organ. 
The name Bacillus noctuarum 6 is used for the bacillus which is here 
shown to be present in the septicemia and the immediate cause of the 
death of the worm. 
Bacillus noctuarum n. sp. 
This species is a facultative anaerobe which grows very well on all of the common 
and differential media ordinarily used in the laboratory. Abundant growth is ob¬ 
tained in media varying in reaction from -f-1.5 to —2 per cent. Less extensive and 
slower growth is obtained from 1 to 2 per cent beyond these limits. Growth may 
be obtained within a considerable range of temperature. That of the room was 
found suitable and was used in most of the work here reported. 
* The specific name of this bacillus was suggested by Dr. I,. O. Howard. 
