On Smut in Wheat. 



liming it, in preventing smut, as recommended in a 

 paper formerly read to the society.^ 

 On Blight, 



The following judicious remarks on blight in wheat 

 by Mr. Marshall, deserve particular attention, on ac- 

 count of the mode recommended of checking the pro- 

 gress of the disease. An experiment of the practice he 

 recommends, is certainly worthy of trial. 



"That the operation of the disease is carried on by 

 the fungus tribe, evidently appears from the labours of 

 botanists. t But fungi it is equally evident, are an ef- 

 fect, not the cause of the disease. They are the vermin 

 of the more perfect vegetables; and fasten on them, 

 whether in a dead or in a diseased state, but seldom, I 

 believe, while they are in full health and vigour. Their 



^ Mr. Wimpey in a paper published subsequent to that re- 

 ferred to page 55^ adduces some facts to shew that this disease 

 in grain, arises solely from the influence of the weather. To 

 the objection to his theory arising from the remark, that in the 

 case of two adjoining fields, one shall be free and the other 

 infected, he replies, "that malignant currents of air, are fre- 

 quently confined to a small space, and affect those objects 

 only that stand in their way : that it is not uncommon to see 

 trees and plants blighted on one side only : and that he has 

 often seen the east and south sides of a field of wheat very 

 smutty when the north and west, and the other parts of the 

 field, have been little affected by it, and sound and smutty 

 ears growing from the same root, and even sound and smutty 

 grains at the same time, in the same ear. He says also, 

 that clean grain will produce a smutty crop, and smutty grains 

 yield a clean produce. This last fact, agrees with the expe- 

 riment of Sir John Call mentioned page 56. 



I See Sir Joseph Banks' paper on blight and rust. 



