Life FH'tforits of }'ar/<i//s Grass Smuts. 



123 



appear as colourless, aiuorphous bodies. These radiating strands become 

 more distinct towards the outside, and their cell-wall is firm and tinted. The 

 spores begin to take shape, and are at first colourless, but gradually assume 

 the olivaceous colour and the globose shape of the mature spores, which are 

 densely packed. In this way all the spores gradually become mature 

 and the diseased grains remain mostly unbroken unless knocked about in 

 harvesting. 



The spores are thus seen to be formed, not simultaneously in the fertile 

 hyphae, but in a progressive mannu- towards the centre, and this mode of 

 formation of spores is characteristic of Cintractia. 



Treatment. 



Clinton^ found hot water treatment of the seed to be a preventive. Field 

 experiments also showed " that the amount of smut ordinarily occurring in 

 broom corn can be greatly increased by mixing a liberal supply of the smut 

 with the seed before planting, but was not increased by planting seed in land 

 that had smut in it or by placing smut on the plants after they appeared above 

 ground." 



No matter whether ordinary or badly smutted seed was treated, the smut 

 was practically prevented. Freeman and Umberger^ have also proved by 

 experiment that formalin, hot water, or bluestone give satisfactory results. 



-!. Brume Grass Smut. 



{Ustilago bromivora (Tul.) F. v. W.) 



Brome smut has been found here on soft brome [Bromus mollis, L.) and 

 prairie grass [Bromus unioloides, Humb.), both of which are imported, and 

 on sand brome {Bromus arenarius, LabilL), which is a native of Australia and 

 New Zealand. It is very general and widespread in its distribution. The 



soft brome is sometimes 

 hundreds of acres. The 



badly attacked that there is hardly a sound oar in 

 leep feeding in such paddocks are sometimes black 



