It would be tedious to attempt anything like a complete account of the estimates of loss in different countries, due to the ravages of insects and fungi, but the following examples should surely serve to convince anyone of the magnitude of these losses and of the economic importance of the whole question, and the reader may be referred to the special literature for further details. The coffee leaf-disease of Ceylon, due to the fungus _Hemileia_, is estimated to have cost that Colony considerably over £1,000,000 per annum for several years. One estimate puts the loss in ten years at from £12,000,000 to £15,000,000. The hop-aphis is estimated to have cost Kent £2,700,000 in the year 1882. In 1874 the Agricultural Commissioner of the United States estimated the annual loss, due to the ravages of insects on cotton alone, to amount to £5,000,000; and in 1882 the annual loss to the United States due to insects, calculated for all kinds of agricultural produce, was put at the appalling figure of from £40,000,000 to £60,000,000 sterling. In India, the annual loss due to wheat-rust alone has recently been estimated at 4,000,000 to 20,000,000 rupees, and one insect alone is said to have cost the cotton planters a quarter of the crop--valued at seven crores of rupees--in bad years. Similarly, in Australia the annual loss from wheat-rust has been put at from £2,000,000 to £3,000,000. In 1891 the loss in Prussia alone from grain-rusts was officially estimated at over £20,000,000 sterling. Need more be said? Even allowing for considerable exaggerations in such estimates it is clear that the damage to crops in any country soon amounts to sums which even at low rates of interest would easily yield incomes capable of supporting the best equipped laboratories and staffs for investigations directed to the explanation of the phenomena in detail, the sole basis on which intelligent preventive and therapeutic measures can be based. But it is far from likely that the estimates are exaggerated. The planting and agricultural communities are as a rule opposed to the publication of statistics--or at least have been so in various countries and at different times--and if we knew the damage done to all crops even in our own Empire, the results would probably astonish us far more than the above figures have done. NOTES TO CHAPTER XV.