120 
COVERED SMUT OF BARLEY, 
On Hordeum vulgare. 
Ustilago hordei (Pers.) Kell. & Sw. 
This smut differs from Ustilago nuda in its method of infection and 
in its appearance in the field. The floral parts are not as completely de- 
stroyed and these serve to confine the spore mass and thus keep the spores 
from escaping until threshing time. Although they have a smooth epi- 
spore they cling to the seed and germinate with it, producing sporidia in 
abundance, laterally and terminally. upon a two to three-septate and 
elongated promycelium. These sporidia send out infection threads which 
penetrate the host in its early stage of growth. The swollen segments of 
isolated promycelium may also produce infection threads. The manner of 
growth in the host and the production of chlamydospores is similar to 
that of other loose smut.', * 
OTHER SMUTS CARRIED OvEeR BY THE SEED OF THETR Host PLANTs. 
Grain Smut of Rice. 
Tilletia horrida Tak. on Oryza sativa. 
Head Smut of Sorghum. 
Spacelotheca Reitiana (Kuhn) Clint. on Sorghum vulgaris. 
Grain Smut of Sorghum. 
Spacelotheca sorghi (LIk.) Clint. on Sorghum vulgaris. 
Grain Smut of Hungarian Grass. ‘ 
Ustilago crameri kom. on Netaria italica. 
Leaf Smut of Timothy, Red-top, Blue-grass, and other Grasses. 
Ustilago striaeformis (West.) Miessi. 
Smut of Tall Oat Grass. 
Ustilago perennans QRostr. on Arrenatherum avenaceum, 
And smuts of many wild grasses. 
LAX WiInt: 
Fusarium lini Bol. on Linum usitatissimum and L. humila. 
The spores of this fungus become attached to the seed and germinate 
with it in the soil. These infect the roots of the young plant, often killing 
the seedling before it appears above ground. In case when plants live and 
1. Clinton, G. P., Smuts of Illinois Agricultural Plants. Ill. Bul. 57, 1900. 
2. Kellerman & Swingle, Reports on the Loose Smut of Cereals. 2d Ann. Rept. 
Kan. Exp. Sta., pp. 313-288 : 1889. 
