than which it ought not to be. The price of bdellium, in its pure state, is three denarii per pound. CHAP. 20.—TREES OF PERSIS. Adjoining the countries which we have previously mentioned is Persis, lying along the shores of the Red Sea, which, when describing[483] it, we have mentioned as the Persian Sea, the tides of which penetrate far into the land. The trees in these regions are of a marvellous nature; for, corroded by the action of the salt, and bearing a considerable resemblance to vegetable substances that have been thrown up and abandoned by the tide, they are seen to embrace the arid sands of the sea-shore with their naked roots, just like so many polypi. When the tide rises, buffeted by the waves, there they stand, fixed and immoveable; nay, more, at high water they are completely covered; a fact which proves to conviction, that they derive their nutriment from the salt contained in the water. The size of these trees is quite marvellous; in appearance they strongly resemble the arbute; the fruit, which on the outside is very similar to the almond, has a spiral kernel within.[484] CHAP. 21. (10.)—TREES OF THE ISLANDS OF THE PERSIAN SEA. THE COTTON TREE. In the same gulf, there is the island of Tylos,[485] covered with a forest[486] on the side which looks towards the East, where it is washed also by the sea at high tides. Each of the trees is in size as large as the fig; the blossoms are of an indescribable sweetness, and the fruit is similar in shape to a lupine, but so rough and prickly, that it is never touched by any animal. On a more elevated plateau of the same island, we find trees that bear wool, but of a different nature from those of the Seres;[487] as in these trees the leaves produce nothing at all, and, indeed, might very readily be taken for those of the vine, were it not that they are of smaller size. They bear a kind of gourd, about the size of a quince;[488] which, when arrived at maturity, bursts asunder and discloses a ball of down, from which a costly kind of linen cloth is made. (11.) This tree is known by the name of gossypinus:[489] the smaller island of Tylos, which is ten miles distant from the larger one, produces it in even greater abundance. CHAP. 22.—THE TREE CALLED CYNA. TREES FROM WHICH FABRICS FOR CLOTHING ARE MADE IN THE EAST. Juba states, that about a certain shrub there grows a woolly down, from which a fabric is manufactured, preferable even to those of India. He adds, too, that certain trees of Arabia, from which vestments are made, are called cynæ, and that they have a leaf similar to that of the palm. Thus do their very trees afford clothing for the people of India. In the islands of Tylos, there is also another tree, with a blossom like the white violet[490] in appearance, though four times as large, but it is destitute of smell, a very remarkable fact in these climates. CHAP. 23.—A COUNTRY WHERE THE TREES NEVER LOSE THEIR LEAVES.