[VoL. 3 
12 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
care as in the ease of the yellowed seedlings grown at higher 
temperatures, at no time was F. conglutinans isolated from 
the roots of these plants. Controls from roots grown at the 
higher temperatures showed the fungus, as has been pointed 
out in previous experiments. Experiments were therefore 
instituted to test whether any such relation might be indi- 
eated by indirect methods. 
The first experiment was started on April 21, 1914, at 
which time twenty pots of infected soil were planted to cab- 
bage, and all were placed on the north side of the potting- 
shed where a low temperature could be maintained. "They 
were kept here until June 6, sixteen days, when all but two 
were placed in House Пе which was being kept at approxi- 
mately 25°C. On June 9, after the pots had remained in the 
warm house for three days, pairs of pots were removed to 
the cooler temperature at intervals of two days until June 
15, after which date a pair was removed each day until June 
19. On June 30 yellows appeared in the two pots removed on 
the last day, June 19, but none was found in any of the other 
pots. This experiment showed that in this case the yellows 
appeared in the same length of time as it usually took to ap- 
pear in a warm house, and would lead to the opinion that 
there had been no infection at the low temperature, or if the 
plants had been attacked, that they were able to recover under 
favorable conditions for growth. 
Coincident with this last experiment, moreover, twenty 
pots of infected soil planted to eabbage were placed in House 
lle, and each day two pots were removed to the cooler tem- 
perature. No yellows appeared in any pots removed in the 
first eight days, but in all those removed subsequently yellow- 
ing was found on June 2. Controls in the warm house showed 
the first symptoms on June 1, one day earlier than those on 
the outside. The cooler temperature, therefore, checked the 
disease in most cases, but where it had gone too far, the only 
effect was a slight lengthening of the period of incubation. 
Later observations on this point do not seem to confirm 
these results. It will be noted that in the experiments car- 
ried on at the Missouri Botanieal Garden, when the plants 
