6 



the wheat head is not determined. AVhen some smut-seeds are placed in a drop 

 of water on a piece of glass, a kind of stem shoots from them, upon which are 

 produced small clusters of elongated, thread-like spores. These become united 

 by short, transverse shoots, and when thus united, these thread-like spores pro- 

 duce other spores, differing in appearance, being thicker and shorter than these 

 threads. The latter produce another kind of spores. "There are still," 

 says a writer, "many points in the history of the growth and development 

 through successive generations of the 'bunt' spores ; but enough is known, on 

 the one hand, to show that this is a true vegetative parasite, and not merely a 

 diseased condition of the tissues of the wheat plant; and on the other, that it is 

 perfectly distinct from all the phases of the other and similar parasitic fungi 

 which affect the wheat crop." 



This statement of the various forms and stages of the growth of smut exhibits 

 a reproduction as singular as that of the aphis, or louse, noticed in the article on 

 the hop plant. But it will be seen that abundant moisture is a condition of its 

 growth, and the want of it is, no doubt, a leading cause why these almost in- 

 finite millions of seeds of the smut fail to reproduce themselves, and thus the 

 wheat crop is saved from entire destruction. 



Are these various stages of the growth and of the production of spores neces- 

 sary to the formation of the seeds or spores, as found in the head of the wheat ? 

 Will the latter only germinate after winter has intervened 1 Are the perfect or 

 last formed spores produced by a growth within or without the wheat plant 1 

 These questions cannot be answered ; but the fact that the sap of the infected 

 wheat plant is much darker than that of the healthy plant, indicates an inward 

 growth, so changing the sap that it produces, through the ovary or germinating 

 part of the wheat, the smut-seed instead of the wheat grain. Has each grain a 

 circulation of sap separate from all others, so that on the same head there are 

 grown wheat and smut? 



If the growth of the spores of smut take place within the wheat plant, how 

 do the parent spores obtain an entrance into it 1 It is supposed that the smut- 

 seed are too large to be taken into the root. Do the second or third forms of 

 these spores obtain an entrance ? If so, how ? Do they find their way through 

 the outer covering of the plant, as the husk of the seed, and, living on its sap, 

 perfect their own growth within the covering of the grain ? Does their presence 

 there cause a discoloration of the sap 1 



These questions cannot yet be answered ; but the only practical object effected 

 by the numerous investigations made in England, France, and Germany, is in 

 the certainty that the smut spores are seeds having a vitality, through which 

 the smut perpetuates itself, and that, by destroying this vitality, the wheat 

 plant can be protected from the smut. 



This can best be done by soaking the wheat-seed in a solution of bluestone, 

 or oil of vitriol, which is sulphate of copper. The effectiveness of this preventive 

 will be seen by the annexed letter from Mr. Haden, near Lexington, Kentucky, 

 As to his suggestion of the cause of smut — that it is an injury from an insect 

 depositing its eggs in the grain of wheat, which hatches the worm described by 



