PLATE i 
A. —A conidial mat i day old. Still increasing its area by active growth on the 
periphery where the pronounced white color is shown. The stromatic mycelium 
which spreads i or 2 cm. in advance of the conidiphores is identical with the charac¬ 
teristic Ozonium form on the roots of infected plants. 
B. —Conidial mats forming in holes made by rodents. Mats on the inside of gopher 
runways have been observed to remain well preserved for a month after the last of 
the fruiting bodies on the surface of the ground had been disintegrated by weathering 
agencies. 
