Oct. 15,1925 Leaf spot of Maize Caused by Ophiobolus Jieterostropbus 717 
Fig. 4.—A (upper). Two mature perithecia of Ophiobolus heterostrophus on diseased maize leaves 
incubated 20 days in a damp chamber, illustrating some variation in size and shape, and 
relationship to conidial fructifications. X 120 
B (lower). Asci in various stages of maturity together with vertically oriented filaments 
that compose the colorless pseudoparenchyma in the interior of the perithecium, which dimin¬ 
ishes with the development of the asci. X 473 
