The patches referred to may bear 500 palm trees to the acre, and these may represent 80 to 100 per cent. of the total tree-growth on the patch. The area of such a patch may be roughly estimated at from ¼ acre to 15 sq. miles, or even more, but it should be added that, where such extensive tracts as these occur, the difficulties of transport and the scarcity of the population have constituted obstacles to working, and to the means of preserving the trees. Oil palms near Mafokoyia are shown in the picture (Fig. 10). [Illustration: OIL PALMS (_ELÆIS GUINEENSIS_), MAFOKOYIA. Fig. 10, p. 21.] [Illustration: NATIVE COLLECTING OIL PALM FRUIT, BLAMA. Fig 11, p. 22.] [Illustration: KOLA TREE AT MANO. Fig. 12, p. 29.] The appearance of a young tree is that of a thick stem throwing out annulate series of long feathery leaf fronds, upon petioles, which bear roughly-formed spines. As the tree increases in height the lower petioles are shed, and the trunk assumes a narrower but more regular form; indistinct rings being traceable, formed by the bases of the fallen leaf stems. A mature tree will measure about one foot in diameter at four feet from the ground, and at the ground surface the diameter will be two and a half to nearly three times as much. The male flowers are collected in the form of a number of tassel-like pendants, springing from a common stalk, and one such bunch is usually found above and upon each side of the female inflorescence. Both sexes of flowers usually occur upon the trees, but the natives recognise the existence of a non-fruiting tree, and one which only produces male flowers. The number of fruit heads and the weight of these vary according to the position, age, and treatment of the tree. An idea may be given of the fruitfulness of trees, from the accounts obtained from natives in different parts of the country. The palm has two fruiting seasons, one during the dry weather and another during the rainy season, the latter being generally the lighter crop. It is estimated that a tree in full bearing will yield from twelve to twenty fruiting heads in one year, each of a fairly large size. A younger tree may only produce four to eight heads, but usually of a larger size; and a tree of only five or six years old may give about the same number of heads, but of smaller dimensions. From very old trees small heads with fruits of a diminished size are obtained. The weight of a moderately large head will be about thirty pounds, and will contain about twelve hundred fruits weighing roughly 23 lbs. An illustration showing two fruiting heads is given (Fig. 9).