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926 by a number of common insects and fungi. The actual enforcement of the order generally would require the services of many thousands of officials, and would be impossible, but it is designed to give powers to the Ministry of Agriculture to proceed against any nursery notori- ous for distributing diseased plants, and also to enable the Ministry to act freely in case of a new pest being introduced.

In America and the British Dominions such legislation is com- mon. It prohibits the possession of diseased plants, the sale of infested plants, the sale of plants from an infested area, the removal from declared areas of plants, cases, bags, packages, earth, manure and even of persons; it is often aimed entirely at nurseries and seeks to control the distribution of plants; nurseries must be regis- tered, must be inspected at fixed intervals, must send out certifi- cates of inspection with all consignments, and may, if infested with a scheduled pest, be quarantined ; and there are the usual provisions as to entry, to prescribing remedies, to penalties for non-compliance. The treatments of infested plants by the owner or by the State are prescribed, or the destruction, isolation or confiscation of infested plants. Further provisions are to compel destruction of insect breeding-places, and to prohibit the planting in infested land or within a certain distance of infested land.

In many countries, as in Great Britain, the occupier of land has to notify the occurrence of any of the scheduled pests to the Min- istry of Agriculture and in some tropical countries there is a specific prohibition of the practice of driving locusts to one's neigh- bour's land. The tendency is to rely less on legislation, compulsion and penalties, and to move more towards education and reason. The spirit which enabled a Government to close all schools, courts, places of business, etc., while a whole province fought locusts, exists only in the least civilized areas of the earth, and the cam- paign against pests is carried on by propaganda, education and the arousing of public spirit.

Insects and Crops. -The importance of insect attacks as factors in the growth of crops varies from the case of cotton, where the insect is a dominant factor, equal in value to soil and climate, to that of rubber, where as yet scarcely any serious insect pest has arisen, certainly none equivalent to the fungoid diseases.

Cotton was formerly produced mainly in the southern United States. There the bollworm was the chief pest, causing loss that now averages some 2,500,000 annually, but in 1894 the Boll Weevil appeared in Texas, and in 1905 Dr. L. O. Howard, Chief of the Entomological Bureau of the United States Department of Agriculture, wrote: -"The Mexican Cotton Boll Weevil has the unique record of developing in less than 20 years from a most obscure species to undoubtedly one of the most important economi- cally in the world. There was a hope that the increase in cotton in the United States would keep pace with the world's demands ; now the weevil has rendered this impossible."

The damage is now averaged at about 5,000,000 annually. But there is worse to come. Another pest has been known in India since 1844; this is the Pink Bollworm, which reached Egypt between 1903 and 1910. There they already had another bollworm; but by 1917 the Pink Bollworm was destroying on the average 17% of the crop, causing a loss of 8,000,000 a year, and this pest reached Texas in 1917. In spite of the efforts of the U.S. Department of Agriculture it was established there in 1921, and in a few years it seems likely to destroy 2,000,000 bales, worth, say, 60,000,000.

Nor are these the only pests of first-rate importance. In India the Spotted Bollworm is a pest which also attacks Egyptian cotton. In 1905 this pest almost entirely destroyed the cotton crop of the Punjab and Sind, and it was known in 1921 only in India, Egypt, the Sudan and British East Africa.

The chief cotton-producing countries are listed here with the pests they have; what if the pests spread to all? The output is that of 1917:

Acres

Bales

Pests

United States of America.

33,841,000

".302,375

H.A.P.E.

India

24,781,000

3,228,800

H.E.

Egypt

China

1,761,000

1,287,000 830,000

P.E.

Russia

(840,000)

578,000

Brazil

400,000

A.P.

Mexico

125,000

A.P.

Peru

110,000

Indo-China ....

20,000

P.

Corea

200,000

Nigeria

2,621

P.

Nyasaland ....

4,448

H.E.

Uganda

20,000

E.

West Indies ....

3,000

P.H.

H Heliothis armigera, the American Bollworm It attacks cot- ton in America but, while it occurs universally in the tropics, does not, in India, attack any cotton but Cambodia.

A Anthonomus grandis Mexican Boll Weevil.

P Platyedra (Gelechia) gossypiclla Pink Bollworm.

E Earias insulana Spotted Bollworm.

Apart from cotton, the actual limiting effect of insect pests is less definite but it is a notable factor in many tropical crops : sugar-cane

suffers heavily from two pests, moth-borers and cane-leaf-hoppers ; the loss from one species alone is, in Barbados, estimated at over I5%- With sugar selling at 15 per ton, this means a loss of 6 per acre, and this loss is avoidable by a small expenditure; but the crop is grown, the expenses of rent, management, cultivation, manur- ing, harvesting, manufacturing are all incurred, on canes diseased and affected by this pest, and the net result is a decreased yield, expenses being still the same, of some 6 per acre.

A similar situation occurs with nearly all crops, but it is difficult to say definitely what proportion of the loss is due to insects. In England, Green Fly may ruin the hops, frequently ruins the plum crop; in America a long cold spring gives the Spring Grain aphis scope to increase, and decreases the yield of wheat and reacts on every wheat sale in the world, or a wet summer destroys Chinch Bug, and the wheat crop increases next year with bigger supplies and lower prices. Of the many factors influencing wheat prices, insects are only a small one, but they may be, in some years, just the determining factor, since the factors of climate, rainfall, weather, production, transport, speculation may all be steady.

Stock Raising, Building and Grain Storage.- Insects are not only factors in crop production but in stock raising, in building protec- tion, and in grain storage. The best example of the first is in the Blowfly pest of sheep in Europe, Australia, S. Africa, Argentina and other places. The loss of stock in Australia in 1916 amounted to 3,000,000, and the production of wool and meat in Australia will depend very much on whether control is obtained over this pest. In 1921 no real effort had been made to control it; but it will eventually be controlled, probably by the introduction of natural enemies and by the employment of substances protecting the animal from attack.

The importance of insects in buildings in Great Britain has been emphasized by the discovery that the glorious timber roof of West- minster Hall was in a dangerous condition owing to the attacks of the Death Watch (Xestobium rufovillosum, or tesselalum). It was found that the timbers were destroyed to a very remarkable extent, and H.M. Office of Works embarked on a scheme of strengthening the roof with an invisible steel frame while preserving intact as much of the timber as possible. It was essential not only to stop the activity of insects but to protect the timber from further infestation, and the solution was found in a treatment by which all infested timber is freed of the pest by dichlorbenzene, and all sur- faces are impregnated with a coat of soap, paraffin wax and cedar- wood oil, which prevents further insect attack. This method has been applied to other buildings, notably St. Paul's Cathedral.

A war problem of importance in which entomology was concerned was connected with the preservation of the accumulated wheat stocks in Australia. In 1917 there was a stock of some three million tons of wheat in bags in Australia, with another similar amount to be harvested. All was stored in the open, since no other storage was possible, the wheat usually being shipped immediately, and the result of storage under bad conditions was an immense infestation by weevil (Calandra oryzae), threatening the complete loss of a stock of wheat urgently required for the Allied countries. Two problems needed to be solved, the storage of wheat and the freeing from weevils of the already infested wheat harvested in 1916 and 1917 and then awaiting shipment. Since the Australian Government were unable to deal with this problem it was necessary for the British Wheat Commission to undertake it, and the solution was found in a method of storage which prevented access of weevil and in a treatment by heat on a large scale, so that in a single plant 1 ,000 bus. per hour were heated for three minutes to I4OF., killing all stages of the weevil and giving a weevil-fr^f wheat suitable for milling and baking. This treatment cost less than one penny per bus. and enabled Australia to ship 200,000,000 bus. of wheat which was otherwise becoming totally unsalable or unusable. (H. M. L.)

ECUADOR (see ).—The population of Ecuador was not altered much during the period 1910–20. Immigration was very slight. No census had been taken. In 1920, an official estimate gave the pop. as 1,500,000.

Government.—In a message to Congress in 1914 President Plaza G. raised the question whether or not presidential government in Ecuador had met the test of experience. Upon that subject he held conferences with the members of a special committee of the Chamber of Deputies and hoped that, as a result of its report, a joint committee from both Houses of Congress would be appointed to draw up a project for the reform of the constitution of 1006. The Senate, however, did not favour this action. President Plaza G. again mentioned the urgent need of constitutional reform in his message to Congress of Aug. 10 1915. Upon the following day he addressed a special message to Congress proposing the political reorganization of Ecuador by the introduction of the parliamentary system. Annexed to his message were certain proposed amendments of Ecuador's fundamental law which were framed to accomplish this end.