Buttons.--The raw materials used for the manufacture of shell buttons are trocha, pearl shell, green snail, and the chambered-nautilus. The Islands have an abundant supply of these shells. They are found in the waters of Jolo and also in the vicinity of Sitanki, and the regions farther north, such as the Tañon Strait and along the coasts of most of the Visayan Islands; some are found along the coasts of Pangasinan and Ambos Camarines. In 1918 the United States alone imported 2,500,000 pesos' worth of buttons; the Philippine exports of this product showed only 251,144 gross in quantity, valued at 231,811 pesos; while the Islands imported buttons worth 119,787 pesos. Japan is supplying one-half of the button importation of America. In 1922, imports were valued at P216,086. There are two button factories in the Philippines. These two companies use only a very small portion of the suitable material that could be obtained. The annual supply of shells which the Philippines produces is 1,000,000 kilograms. The two local factories use less than 300,000 kilograms a year. This limited local demand for shell and the better prices offered abroad result in the Philippine supply of shells being exported to other lands. It is estimated that a small button factory, destined only for the local trade and capable of producing fifty gross of buttons daily, would require an investment of about 20,000 pesos, exclusive of the cost of buildings. PUBLIC LANDS There are approximately 73,214,742 acres of public land in the Philippine Islands. Of this area 41,029,900 acres are considered suitable for agriculture, while the total area applied for as homesteads, lease, and sale concession amounts to only 3,159,712 acres. There are still 37,870,188 acres of agricultural domain that have not yet been appropriated. In the Province of Cotabato alone on the great Island of Mindanao, there are still 3,578,169 acres of agricultural public land not yet occupied nor applied for, and in the Province of Samar, one of the Visayan group, 2,524,388 acres. In the Island of Mindanao and the Sulu Archipelago may also be found some of the most suitable agricultural lands for growing rubber, hemp, coconut, rice, tobacco, and other staple products, which are available to the farmers at practically no expense. The various modes of acquiring public land are explained below. Homestead.--Any citizen of the Philippine Islands or of the United States, over the age of 18 years, or the head of a family, who does not own more than 59 acres of land in the Philippines may enter a homestead of not exceeding 59 acres of agricultural land of the public domain. Upon the filing of an application and approval thereof by the Director of Lands, possession may be taken of the land applied for upon payment of $5 as entry fee.