776 
VERANUS A. MOORE. 
facts have been pointed out, (i) that the udder is normally more 
or less extensively invaded with bacteria and, (2) that certain 
species of bacteria seem to persist in the milk ducts of the 
glands when once they become lodged there. If these results 
apply to cows generally as rigidly as they did to the udders we 
have examined, an explanation for the presence of a variety of 
bacteria in the affected glands is not difficult to find. Whether 
these particular organisms would, under certain conditions, be¬ 
come primarily responsible for udder disease is not known. The 
evidence is not conclusive that a number of the bacteria hereto¬ 
fore described as the cause of mammitis were not in the affected 
glands by virtue of their presence in the normal udder. Con¬ 
cerning these points additional investigations are much needed. 
Material from two quite serious outbreaks of mastitis has 
come to our laboratory for examination. In both instances the 
trouble was investigated by Dr. W. H. Kelly, under authority 
of the State Commissioner of Agriculture. In the first out¬ 
break, the milk was drawn in sterile bottles after the udders 
and the hands of the milker had been thoroughly washed in a 
1 to 1000 solution of corrosive sublimate. In all, there were 
eight samples of milk taken from as many different cows. 
These were carefully examined bacteriologically. In six of the 
eight specimens streptococci appeared in pure culture. In the 
agar plate cultures made from the milk from the other two 
cases colonies of micrococci were associated with the strepto¬ 
coccus. 
In the second outbreak the milk was drawn with aseptic 
precautions directly into tubes containing slant agar. Milk 
from four cows was thus taken and brought directly to the lab¬ 
oratory where it was carefully examined. A number of cul¬ 
tures were made from each tube. The media inoculated from 
two of the original cultures (milk) developed into pure cultures 
of streptococci, and those from the other two were impure, but 
contained the streptococcus. The streptococci obtained from 
all of the twelve cases in the two outbreaks appeared to be 
identical and the clinical aspect of the disease in the different 
