New York AGRICULTURAL EXPERIMENT StaTION. 145 
determined. The results led us to abandon further work with 
formalin. 
After the preceding work with formalin was completed, 
however, Spieckermann’s article (1902: 166) reached our hands 
in which he reports that a 0.2% solution of formalin sterilized 
the cultures of the soft-rot organism of cabbage with which 
he was working and did not inhibit the action of the cytolytic 
enzym, at least for several hours. We, therefore, undertook 
to learn the relative rate of action of formalin upon each, 
B. carotovorus and its enzym, by adding to broth cultures 
0.2% of formalin, shaking thoroughly and testing both viability 
and enzym action at frequent intervals. It was found in the 
first series of trials that at the end of twenty-four hours the 
activity of the enzym was not appreciably lessened, at the 
- end of forty-eight hours there was slight retardation and this 
was pronounced at the end of seventy-two hours. On the 
other hand transfers at the end of only three hours showed 
most of the organisms to be dead or so affected that growth 
was slow in starting and at the end of forty-eight hours the 
broth was sterile. 
In a second series of trials the broths were tested at more 
frequent intervals. This again showed the organisms to be 
killed before the enzym was fully destroyed, but the retarda- 
tion was more pronounced than in the preceding trials. The 
details are as follows: : 
1. Action on enzym:—Broth cultures six days old; for- 
malin added to make 0.2% solution, thoroughly shaken; cyto- 
lytic action compared with control tubes by testing upon thin 
sections of turnip. Result: After three hours slight retarda- 
tion was evident; after six hours nearly twice as long a time 
was required for the same results in the formalin solution, 
i. e., formalin retarded the action 50%; after twenty-four 
hours still more difference; after forty-eight hours formalin 
solution required five times as long as control; after eighteen 
days it required sixty hours to disorganize sections, whereas 
the control broth did this in one hour. 
In a third series, little if any retardation up to the sixth 
hour; after nine hours the action of the formalin broth re- 
