Ecological Relations of the Smut of Maize. Plate 3 
I Figs. A, B, C, and D, photomicrographs of colonies of Ustilago zeae on carrot agar plates, two 
days old from conidial sowing at 20° to 22° C.X about 100. 
A. —Small colony, isolation L 44c. 
B. —Large colony, isolation L 44c. , 
C. —Small colony, single spore (chlamydospore) isolation of Ustilago zeae for comparison with A. 
D. —Large colony of U. zeae (from chlamydospore) for comparison with B. 
Figs. E and F—Photographs about one-half natural size. 
E. —Plant inoculated with culture No. 88, in the same manner as described for cultures Nos. 6c 
and 79 in legend of Plate 4. 
F. —Cultures of U. zeae. Note the rugose surface. 
