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C. A. LUDWIG 
smoke at the bottom of the slant and progressed gradually upward. 
The colony in the washed smoke covered the surface of the agar in 
considerably less time than that required by the one in raw smoke. 
Cryptococcus Ludwigi. — In neither trial did the colony of this yeast 
in the raw smoke reach the top of the agar slant by the end of the 
exposure, although the colony in the treated smoke did reach that 
degree of development. As with most of the other organisms, the 
development proceeded from the bottom upwards. 
Penicillium stoloniferum. — The development of this green mould 
was retarded in both the treated and untreated smoke, Conidia were 
produced normally. By the end of the y-day period the colony had 
reached the top of the slant in washed smoke while in the unwashed 
smoke only the lower half was covered. 
The results w4th the following eight organisms are based on two 
trials with washed smoke and the same number with unwashed smoke. 
Bacterium stewarti. — With B. stewarti the washed smoke, as usual, 
was less toxic than the unwashed. In the test with untreated smoke 
the area in which the colony had developed to visibility was still 
limited to a rather small area at the base of the slant at the end of the 
6-day exposure. 
Bacillus carotovorus. — The colony of B. carotovorus in raw smoke 
had developed on ^ to ^ of the agar slant by the end of a week. In 
washed smoke, however, it had extended the entire length of the slant 
in 4 and 6 days respectively. 
Bacillus melonis. — The colony of B. melonis was visible within a 
day after inoculation in washed smoke, but it required 2 days and 4 
days respectively to become visible in the other. In the latter condi- 
tion, also, the colony had not reached the top of the slant at the end 
of 6 days in either trial. 
Bacillus campestris. — In the first test with raw smoke it took 2 
days for the colony of B. campestris to become visible and it had 
progressed upward only about i cm. at the end of 6 days. In the 
second test for some unknown reason the culture failed to grow at all. 
In the treated smoke the colony was visible in one day and it had 
reached the top of the slant in 6 days. 
Bacterium tumefaciens. — The colony of B. tumefaciens in untreated 
smoke did not become visible before 2 days in the more vigorous culture 
of the two, and in both cases was still confined pretty closely to the 
base of the slant at the close of the 6-day period. The cultures in the 
washed smoke grew more vigorously. 
