226 
[Vor. 4, 1917] 
ANNALS OF THE MISSOURI BOTANICAL GARDEN 
EXPLANATION OF PLATE 
PLATE 14 
Fig. 1. Effect of low temperature (45° Е.) upon the develop- 
ment of the mosaic disease of tobacco: a, old leaf still showing 
mosaic; b, young leaf NS very slight venation at the tip, but 
otherwise normal; c, older leaf showing slight venation, but no 
mottling. 
Fig. 2. Effect of »- temperature (85° F.) upon the develop- 
ment of the mosaie disease of tobacco: a, young leaf showing vena- 
tion; b, older leaf sho қынай venation changing to mottling; о, old 
leaf showing mottling. This leaf is about the same age as leaf с in 
fig. 1. 
fake ы E change from venation to mottling, temperature 
e venation still present in tip of leaf, but otherwise 
mottled т. келмедің leaf venated throughout. 
