PLATE 13 
Helminthosporium stenacrum 
Aa-r.—Conidia from leaf of Agrostis stolonifera showing variation in size, shape, 
and septation. In Ag, h, i, I, 0, q, r, distal portion produced as a somewhat attenuated 
prolongation, in which septa are absent or present in smaller numbers than in unmodi¬ 
fied region. X500. 
Ba-c.—Conidia from leaf of Agrostis stolonifera germinating in water by the pro¬ 
duction of germ tubes from both middle and end segments. X500. 
Ca-b.—Conidiophores of H. stenacrum showing variation in size and mode of emer¬ 
gence singly or in pairs from between adjacent epidermal cells. X500. 
