coagulates it to rubber, which is made into round flat cakes. A large tree, five feet in diameter, will yield when first cut about twenty gallons of milk, each gallon of which makes two and a half pounds of rubber. I was told that the tree recovers from the wounds and may be cut again after the lapse of a few months; but several that I saw were killed through the large Harlequin beetle (Acrocinus longimanus) laying its eggs in the cuts, and the grubs that are hatched boring great holes all through the trunk. When these grubs are at work you can hear their rasping by standing at the bottom of the tree, and the wood-dust thrown out of their burrows accumulates in heaps on the ground below. The government attempts no supervision of the forests: any one may cut the trees, and great destruction is going on amongst them through the young ones being tapped as well as the full-grown ones. The tree grows very quickly, and plantations of it might easily be made, which would in the course of ten or twelve years become highly remunerative. We left Castillo at daylight the next morning, and continued our journey up the river. Its banks presented but little change. We saw many tall graceful palms and tree ferns, but most of the trees were dicotyledons. Amongst these the mahogany (Swietonia mahogani) and the cedar (Cedrela odorata) are now rare near the river, but a few such trees were pointed out to me. High up in one tree, underneath which we passed, were seated some of the black congo monkeys (Mycetes palliatus) which at times, especially before rain and at nightfall, make a fearful howling, though not so loud as the Brazilian species. Screaming macaws, in their gorgeous livery of blue, yellow, and scarlet, occasionally flew overhead, and tanagers and toucans were not uncommon. Twelve miles above Castillo we reached the mouth of the Savallo, and stayed at a house there to breakfast, the owner, a German, giving us roast wari, fowls, and eggs. He told me that there was a hot spring up the Savallo, but I had not time to go and see it. Above Savallo the San Juan is deep and sluggish, the banks low and swampy. The large palm, so common in the delta of the river, here reappeared with its great coarse leaves twenty feet in length, springing from near the ground.