SCIENTIFIC COMMITTEE, MARCH 23. 



xxxvii 



colour of the crop. " It is only a few years ago — a very few 

 when one looks back upon it — that our attention was drawn by 

 Mr. J. L. Jensen of Copenhagen to the fact that there are two 

 distinct kinds of smut upon Barley. At first there was a con- 

 siderable disinclination to regard these two smuts as being due 

 to two distinct species of Ustilago ; but since they are not only 

 easily distinguishable by the unaided eye, but also differ in the size 

 and form of their spores, and as the latter have been found to 

 germinate in a totally distinct manner, there is now no doubt 

 about it. Our American confreres at the time repeated the 

 protective measures suggested by Mr. Jensen, and confirmed their 

 efficacy ; but here the matter stopped, for the simple reason that 

 the damage done by smut was trivial, and from a monetary point 

 of view the dressing of seed Barley was a needless expense. A 

 few days ago a circumstance came under my notice which 

 materially alters the complexion of the case. A gentleman who 

 is rather an extensive grower of Barley in West Norfolk drew my 

 attention to the fact that two years ago his Barley was of an 

 excellent colour, while it was in the stack ; but when it was 

 threshed it was so discoloured that he had to accept a very low 

 price indeed for it. He attributed the damage in colour to the 

 number of smutted ears which remained intact when the crop 

 was harvested, but which, by being broken up in the process of 

 threshing, discoloured the whole sample, just in the same way as 

 bunted Wheat does. Fortunately he had kept some of this 

 discoloured Barley. On inspection it looks as if it had been 

 damaged by exposure to the weather. When a little of it, how- 

 ever, is shaken in a test tube with clean water the water becomes 

 discoloured, and a drop placed under the microscope is seen to 

 be full of Ustilago spores. So convinced was this gentleman of 

 the cause of the discoloration that in the next season he dressed 

 his seed Barley with the ordinary sulphate of copper dressing, 

 which is used for seed Wheat for the prevention of bunt. The 

 result was eminently satisfactory; for that year his crop was 

 free from the disease, and the grain, of good colour, realised a 

 proportionately good price. The ordinary Ustilago carbo, as it 

 used to be called, has no detrimental effect on Barley, beyond 

 destroying a certain percentage of plants, its spores being all blown 

 away long before the harvest ; but with the species in question, 

 which, by the way, has received already a considerable number 



