1916] 
GILMAN—CABBAGE YELLOWS 67 
TABLE XI 
AMOUNT OF YELLOWS PRESENT AFTER AN EXPOSURE OF THREE 
WEEKS TO HIGH AND LOW TEMPERATURES 
After three weeks’ exposure 
Pot Total 
Soil Tem- o о No. P 
perature plants diseased diseased 
еба. Ube C. 73 27 37 
pil 7. i ror 5 К 25; C. 69 25 38 
S Iu ntected. a coo m ет РС, 60 16 21 
ek EE Mes 2w C. 54 20 37 
ес WE E DuC. 44 18 41 
Let EE E 15-20? C. 60 0 0 
7 succ) pr ИТТЕР MI 15-20? C. 49 0 0 
8 |Emmected ..... AV ERËN 6 2b. C. 119 0 0 
Есей e. 15-20? C. 58 0 0 
Again, on February 21, the effect of transplanting normal 
plants to infected soil at different temperatures was tried. 
Fifty normal plants were placed in two flats of infected soil 
February March 
22 „24. 83 27 2 2 3 4 f$ 6 7 40 // /2 E 74 /$ 
> 
Ki 
~ 
9 
to 
° 
I 
° 
Percentage of disease Degrees Centigrade 
ч 
9 
Fig. Ка Comparison of soil temperatures in House Ile and those in House 
p^ with the occurrence of yellows in the respective houses; House Ile, bro- 
n line; House Ila, solid line. 
E one flat placed in each house. Controls consisted of ten 
normal plants from the same flat as the above, placed in nor- 
mal greenhouse soil in two pots, one pot in each house. Soil 
