SOME MODERN ASPECTS OF APPLIED BOTANY 29 
harvest of wheat, oats, and rye amounted to £20,628,147. In 
Australia the loss in wheat in 1891 caused by rust was estimated 
at £ 2,500,000. 
The coffee-leaf disease of Ceylon caused by the fungus //emileia 
was stated by Professor Marshall Ward to have cost Ceylon over 
a million pounds per annum for several years. He further states 
in his book on Disease in Plants that one estimate puts the loss 
in ten years at from 12,000,000 to £15,000,000. He further 
states that the Hop Aphis is estimated to have cost Kent 
4#2,700,000 in the year 1882. If the recent outbreak of goose- 
berry mildew of the American type had not been scheduled under 
the Destructive Insect and Pest Act, and arrested, it would no 
doubt have wiped out the gooseberry crop throughout the country. 
Mr. E. S. Salmon states that the average annual value of the goose- 
berry crop in Kent, Wisbech, Evesham, Calstock, and Gloucester- 
shire is from £97,000 to £160,000 in these districts alone. Also, 
that the value of the gooseberry crop to cottagers, private gardeners, 
etc., is incalculable. It was principally through his energy and 
influence that the disease was scheduled. 
At the British Association this year Messrs. Barker and Hillier 
described a disease known as Cider Sickness, that causes a loss 
probably amounting to several thousand pounds sterling each year 
in the West of England alone. It is brought about by a bacterium. 
A destructive bacterial disease of the banana and plantain has 
recently been discovered in the West Indies. The disease causes 
the leaves to become yellow and drop off. The terminal bud is 
eventuaily killed and the whole plant rots down to the ground. 
The organism responsible for this has been isolated, and is being 
provisionally called Bacterium muse. 
A disease like this might easily become epidemic and ruin the 
cultivation of the banana in the West Indies, in the same way as 
the coffee-leaf disease ruined the coffee industry in Ceylon. 
I need not comment further on the loss that would result if plant 
pathologists were not on the spot, studying and devising means to 
prevent such a catastrophe. 
If we had any means of estimating the loss caused annually by 
the dry-rot fungus, the figures would no doubt be equally astounding. 
We have very little means of estimating cases of annual loss in 
this country due to disease, but the total must be enormous. 
Reference to the failure for some years and threatened extinction 
of the potato crop in Ireland about sixty years ago, with its attendant 
loss and suffering to millions of people, may recall the seriousness of 
an epidemic disease of a food plant. Since then preventive means 
in the shape of spraying have been devised, thanks to the develop- 
ment of applied botany, whereby the disease may be kept sufficiently 
in check to prevent a repetition of such a dire calamity. 
Within recent years an entirely new potato disease was discovered 
by Schilberskzy in Upper Hungary, namely, the Black Scab disease, 
which is caused by a fungus, Chrvsophlyctis endobiotica. In 1901 
