Aug. 15, 1914 
Head Smut of Sorghum and Maize 
347 
All the plants represented in figure 1, except O, were dissected in 
the early autumn of 1910 at Amarillo. Plant O was one of a number 
prepared in 1911. In plants A to K, inclusive, no buds were taken from 
below the surface of the ground. In all cases, however, the exact position 
of the ground line was not recorded, but has been assumed. The buds 
on the suckers shown in plant P were not necessarily situated as shown, 
since they were too small to differentiate by the method used. Culm P3 
also bore a sucker at the first node, on which three buds were infected 
and three apparently undiseased, the apical bud being lost. 
Fig. a.—Diagram of Plate XXXVII, figure i, showing the position of the hyphae. 
An examination of the diagrams reveals the fact that most of the culms 
were but partially infected. A particularly noticeable feature is that 
when only a few of the buds were missed by the parasite they occurred 
neither at consecutive nodes nor yet irregularly, but almost without 
exception included only such as were on the same side of the culm. This 
is well illustrated in culms A2, D3, Ei, E4, Fi, J4, and L,i. In the same 
way, if only a few of the buds were involved in the infection, they, too, 
were usually on the same side of the culm and at the base of the plant, 
as seen in culms Di, D4, and F2. The basal portion sometimes escaped 
(as in culms K2 and M2), and occasionally the top grew away from the 
