To return, however, to our Humming-birds, of which my readers will like to have one or two more described,--_la crême de la crême_, the very _élite_ of this lovely little fairy population. If we were to cross the Atlantic to Brazil, track up the mighty Amazon some thirty days' sail, and a distance of a thousand miles, we should come to the mouth of the Rio Negro, where a remarkable change in the appearance of the water indicates a totally different region. Instead of the muddy water of the Amazon, resembling pea-soup, that of the Negro is intensely dark, but clear and limpid, every ripple sparkling like crystal. The land becomes high, and the river, some four miles wide, passes between lofty cliffs, crowned with the rich green walls of the primeval forest. The country is far more attractive than that on the Amazon; instead of a dead level, swampy and intersected by sluggish _igaripés_, or shallow ponds, overhung by impenetrably tangled thickets, and full of venomous flies, here are gentle hills, and tiny brooks of sparkling water, and a comparatively open forest, with bright clear glades in which the traveller may recline without persecution from the flies,--these pests being unknown on the "black waters." The ground is covered by evergreens of different species and exquisite forms, and many kinds of elegant ferns are growing in the valleys. There are few lianes or spinous briers stretching from tree to tree, obstructing free passage, but a thousand lesser vines drape the low tree tops with myriads of flowers, new and attractive to the visitor. Everywhere the forest is intersected by paths, some made by the inhabitants in their frequent rambles, others by wild animals that come to the water to drink; and along these the eager naturalist can readily pass to the feeding trees of many beautiful and peculiar birds.