120 



Covered Smut of Barley, 



On Hordeum vulgare. 



Ustilago hordci (Pers.) Kell. & Sw. 



Tins 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. 1 , 2 



Other Smuts Carried Over by the Seed of Thetr Host Plants. 

 Grain Smut of Rice. 



Tilletia horrida Tak. on Oryza saliva. 

 Head Smut of Sorghum. 



Spacelotheea Beitiana (Kuhn) Clint, on Sorghum vulgaris. 

 Grain Smut of Sorghum. 



Spacelotheea sorghi (LK.) Clint, on Sorghum vulgaris. 

 Grain Smut of Hungarian Grass. 



Ustilago crameri Koin. on Setaria italica. 

 Leaf Smut of Timothy, Red-top, Blue-grass, and other Grasses. 



Ustilago striaeformis (West.) Miessl. 

 Smut of Tall Oat Grass. 



Ustilago perditions Rostr. on Arrenatherum avenaceum. 

 And smuts of mauy wild grasses. 



Flax Wilt. 



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. 111. Bui. 57, 1900. 



2. Kellerman & Swingle, Reports on fehe Loose Smut of Cereals. 2d Ann. Re^pt. 

 Kan. Exp. Sta., pp. 313-288 : 1889. 



