New YorkK AGRICULTURAL EXPERIMENT STATION. 117 
Indol. The production of indol by this collection of cul- 
tures is slight in all cases and the various observers have not 
always considered that the red color produced by the test was 
sufficient to be considered positive. However in both labora- 
tories series of tests have been considered as sufficiently de- 
cided to be classed as positive. It will be noted that this 
result is not in accord with the record of Townsend”? with 
B. aroideae, but the disagreement is undoubtedly a matter of 
interpretation of results rather than a difference in organisms. 
Nitrate reduction. It was only in a few instances that the 
reduction of nitrates was not detected in the standard solu- 
tions. In all of these instances succeeding cultures showed 
the characteristic color reaction. The cultures which failed 
had not been revivified previous to the test. 
Gas formation. As has already been indicated the gas for- 
mation from dextrose, lactose and saccharose in the fermenta- 
tion tube offers a basis for classifying this collection of cul- 
tures. Owing to the importance of the observation on this 
point and to the somewhat conflicting results obtained with 
some of the cultures, the results of the various determinations 
are here given in Table ITT. 
23 Townsend, C. O._ loc. cit. p. 32. 
