=Corn.=--Maize or Indian corn is the seed of a plant, _Zea mays_, a member of the grass family. It is not known to exist in a wild state. The species now cultivated are undoubtedly derived from the American continent, but evidence is not wanting to show that it was known in China and the islands of Asia before the discovery of America.[29] The commercial history of corn begins with the discovery of America. Next to meat it was the chief food of the native American; next to wheat it is the chief food-stuff in the American continent to-day. Corn requires a rich soil and is not so hardy as wheat. It thrives best in regions having long summers and warm nights. The growing crop is easily injured by too much rain. It is an abundant crop in the central Mississippi Valley, but not near the coast; it is very prolific in Nebraska, but not in Dakota; it thrives in Italy, Austria, and the Balkan Peninsula, but not in the British Isles and Germany. It is a very important crop in Australia, and is the staple grain of Mexico. It is the crop of fourteen-hour days and warm nights. [Illustration: CORN] The United States is the chief producer of corn, and from an area of 80,000,000 acres--about that of Ohio, Indiana, and Illinois combined--more than two billion bushels, or four-fifths of the world's crop, are produced. In the past few years the area planted with corn has not materially increased, and it is likely to be lessened rather than increased in the future. From the same acreage, however, the annual yield, now about twenty-five or thirty bushels per acre, can be more than doubled by the use of more skilful methods of cultivation. Corn contains more fatty substance, or natural oil, than wheat, and therefore has a greater heating power. For this reason it is better than wheat for out-of-door workers, and it is almost the only cereal food-stuff consumed in Spanish America. It is also a staple food-stuff in Egypt. Corn has been used as a bread-stuff in the United States, Italy, and Rumania[30] for a long time. In recent years, however, its use has become very popular in Europe. [Illustration: CORN PRODUCTION] In the United States by far the greater part of the crop is consumed where it is grown, being used to fatten swine and cattle. The market value of a pound of corn is about one-third of a cent; converted into pork or beef, however, it is worth five or six times as much. By feeding the corn to stock, therefore, a farmer may turn an unmarketable product into one for which there is a steady demand. [Illustration: CORN]