Lower down we saw numerous islands, some of large size and of a peculiar formation. The river, which had risen so rapidly a few days before, had gone down to its normal level and left these obstructions in the channel exposed high above the surface. A matted mass of logs and branches of which a layer fifteen feet thick protruded above the water, formed the base of the islands; on this soil had gathered to a depth of five or six feet, and supported a luxuriant growth of vegetation. These islands are composed of deposits of driftwood which were left stranded on sand-banks during the season of high water, and while the edges are torn and jagged the force of succeeding floods seems to be of insufficient strength to wash them away. As we paddled along quietly near the banks the priest or the Indians pointed out many interesting and curious plants. One of these is the _palo santo_, or holy tree; it grows to be a great height, but the trunk is comparatively slender. The peculiar name is derived from the fact that it is as carefully guarded as any sacred object should be, but in this instance by myriads of fire-ants, which live in the hollow interior of the trunk. If the tree is struck sharply with a stick the ants pour out in endless files through minute openings. They are vicious insects, and the bite smarts and burns many hours after it is inflicted. The _tacuara_, a species of tall, feathery bamboo, is another interesting plant of this region. When the stalk is cut down the leaves shrivel and dry within a few minutes. Large numbers of cabbage-palms grew throughout the forest. The beautiful, plume-shaped leaves droop in a great umbrella-like mass from the top of a column sixty or seventy feet high; thick clumps of straight, tough roots branch out eight or ten feet above the ground and form a solid support to the stem. A delicious salad is made from the tender leaves, folded up in the bud; or if boiled the flavor is similar to that of asparagus. To secure the bud it is, of course, necessary to cut down a tree which has taken the greater part of a century to mature, but in a region where many millions are growing one is not inclined to be sentimental, and will only bemoan the fact that it requires an hour’s hard work to chop through the steel-like trunk before the coveted morsel is brought down.