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BACTERIA IN THE DAIRY. AT 
specimens have been received from the same place. ‘Ihe Rhode 
Island locality was very carefully studied. Milk was collected 
from twelve dairies in this section, in as fresh a condition as 
possible. In four samples it was taken direct from the teat. 
From most of the dairies many samples have been received, 
some of mixed milk, others from one cow. 
Thirty dairies have furnished fifty-three samples of milk, 
from which one hundred and eleven colonies have been isolated. 
Thirty-four of these were discarded as not producing acid, or 
as nearly anaerobic. Of the seventy-seven studied, forty-seven 
of them appeared to be the same species. Although the an- 
alysis of these forty-seven severally is not identical in some of 
the minor details, yet in the most important distinctions they 
agree. The distinctive character of this species is the power 
of curdling milk in a very short space of time. The actual 
limit has not been determined; but sterile milk inoculated 
with a small amount of culture, placed at thirty-five degrees 
centigrade, was examined in twelve hours and found to be 
thoroughly curdled. At the normal room temperature it cur- 
dles milk in from sixteen to thirty-six hours. 
Along with this species, and supposed to be the same when 
first picked out, were ten others, which in all the culture tests 
seemed to be identical in character with the forty-seven, with 
the exception that they did not curdle milk, although they did 
make it acid. Some rendered milk strongly acid, others weakly 
acid. ‘These facts seem to suggest that they are the same spe- 
cies as the forty-seven, but that these ten had lost the power 
of curdling milk. 
Of the twenty remaining organisms ten were aerobes and 
produced acid sufficient to curdle milk. ‘Three of these were 
the same species, one coming from Ohio, and the other two 
from Massachusetts. ‘These aerobic acid organisms were taken 
from six samples. ‘The forty-seven facultative anaerobic acid 
curdling specimens, which were alike, were found in the fifty- 
three samples of milk studied. 
III.—TECHNIQUE OF EXPERIMENTS AND ANALYSIS OF THE 
PRINCIPAL ORGANISM. 
Ordinary peptone-gelatine was prepared, to which was added 
3 per cent. of milk sugar and dry blue litmus, in the propor- 
tion of one to thirty parts of the culture medium. The gelatine 
