The beauty of the forest that bordered the river was a never-ending source of attraction to our friends. Giant trees and trees of lower stature covered the banks, and extended back from the shore as far as the eye could reach. Their trunks were almost concealed by the profusion of climbing plants, and their foliage was intermingled with bright orchids, some of immense size, and with colors rivalling those of the rainbow. The variety of the trees and plants was bewildering, and as our friends gazed hour by hour upon the ever-changing panorama, with its ever-sameness, they realized that it would be a labor of years for a botanist, to number and classify the vegetable growths comprised in the limits of a single day's travel. [Illustration: LEAVES, NUT, AND FLOWERS OF SAPUCAYA, AN AMAZON TREE.] Fred copied into his note-book the following, from Professor Orton's narrative: "No spot on the globe contains so much vegetable matter as the valley of the Amazon. In it we may draw a circle a thousand miles in diameter, which will include an evergreen forest broken only by the rivers and a few grassy _campos_. There is a most bewildering diversity of grand and beautiful trees--a wild, unconquered race of vegetable giants--draped, festooned, corded, matted, and ribboned with creeping and climbing plants, woody and succulent, in endless variety. [Illustration: FERNS, TREES, AND CREEPERS.] "The flowers are on the top. On many of the trees not a single blossom is to be found at a height less than one hundred feet. The glory of the forest can be seen only by sailing in a balloon over the undulating flowery surface above. There, too, in that green cloud, are the insects and birds and monkeys. You are in 'the empty nave of the cathedral, and the service is being celebrated aloft in the blazing roof.' In place of mosses and lichens, the trunks and boughs are bearded with orchids, ferns, tillandsias, and cactuses, frequently forming hanging gardens of great beauty. The branches are so thoroughly interwoven, and so densely veiled with twiners and epiphytes, that one sees little more than a green wall. He might roam a hundred years in the Amazon thicket, and at the end find it impossible to classify the myriad crowded, competing shapes of vegetation. The exuberance of nature, displayed in these million square miles of tangled, impenetrable forest, offers a bar to civilization nearly as great as its sterility in the African deserts." CHAPTER XIX. FROM THE MADEIRA TO THE RIO NEGRO.--OTHER TRIBUTARIES OF THE AMAZON.--NOTES ON THE GREAT RIVER.--MANAOS.--DOWN THE AMAZON TO PARA.