PLATE 2 
A. —A type of curly-top beet leaf. Note the inconspicuous rounded swelling 
scattered over the surface. 
B. —Curly-top beet leaf. Note the general distribution of the moderate, irregu.. 
lar swellings on the smaller veins. This specimen is representative of one type 
of response to the disease stimulus. 
C. —Exudate on a curly-top leaf. The clear, viscid exudate has a sweet taste 
Fehling’s test reveals the presence of sugars after hydrolysis with acid. 
D. —Sugar beet curly-top. Plant inoculated on July 19,1918, and photographed* 
on August 29, 1918. Note the length of the old leaves, which were about mature? 
when the plant was infected, in contrast with the dwarfed younger leaves. 
