228 
[Vor. 4, 1917] 
ANNALS OF THE MISSOURI BOTANICAL GARDEN 
EXPLANATION OF PLATE 
PLATE 15 
ig. l. Effect of temperature on the development of the mosaie 
pre of tobacco. Plants 0 and с, grown at a temperature of 
5-75° Ж; аге the same age. Plant b is apparently affected with 
m 
1916. Plant a shows b on е 13, 1916, after having bee 
kept at a temperature of about 40° Е. and illustrates meer 
recovery. 
Fig. 2. An old diseased plant transferred to the greenhouse in 
the fall. Shoots а and b appeared while the о was low 
(about 40-45° Е.) and illumination poor, and not show 
mottling. Shoot с appeared while the non us was "high (about 
60-70* F.) and sunlight more abundant.  Slight mottling is 
evident. 
