Page:Popular Science Monthly Volume 61.djvu/499

Rh only deficient in indigenous food plants and animals, but the natural conditions are distinctly unfavorable to agriculture.

The whole surface of these flat coral islands is like the clean white-sanded floor of an old English kitchen. The cocoanut tree springs up everywhere, but in the spots where yams and taros are grown the sand is hollowed out, and a pit formed, from one to two hundred yards long, and of varying width, into which decaying cocoanut leaves and refuse are thrown, till a rich soil is formed.

It is certain, however, that among the Polynesians the cocoanut is a cultivated plant no less than the yam, taro, sweet-potato, sugar-cane, banana, breadfruit and numerous other species found in use throughout the tropical islands of the Pacific. Moreover an especial interest attaches to the cocoanut in that there are adequate botanical reasons for believing that it originated in America, the home of all related palms.

The agricultural achievements of the Polynesians become the more impressive when we reflect that so many of their cultivated species were not propagated from seeds, but from cuttings. To survive the long voyages in open canoes, these must have been carefully packed, kept moist with fresh water and protected against the salt spray. In the present state of botanical knowledge the number of species thus introduced and distributed by the Polynesians is necessarily uncertain. Many of the economic plants were native in some of the islands of the Pacific, though their constant presence among the peoples of widely separated archipelagos gives sufficient reason for including them in the list of twenty-four species, which Professor Hillebrand believes to have been brought to the Hawaiian Islands by the early Polynesians. This number, however, must be greatly increased, since there were many varieties of the sweet potato, taro, sugar-cane and banana. Moreover the Hawaiian group is scarcely more than subtropical in climate, and lacks numerous seedless sorts of the breadfruit, yam, taro and other plants of the equatorial belt of islands, so that a complete enumeration of the species and varieties carried by the Polynesians would include nearly a hundred.

A detailed study of the distribution, names, cultures and uses of these species and varieties of tropical economic plants would yield information of much value from the agricultural standpoint, but of even greater significance is its bearing upon the origins and migrations of