locked it up carefully for the night, not knowing what other titbits might be coveted by the superstitious inhabitants. _December 18th._—In the midst of the zoölogical work, the collection of palms, which is now becoming very considerable, is not forgotten. This morning we went into the forest for the purpose of gathering young palms to compare with the full-grown ones, already cut down and put up for transportation. In these woods a thousand objects attract the eye, beside that which you especially seek. How many times we stopped to wonder at some lofty tree which was a world of various vegetation in itself, parasites established in all its nooks and corners, sipos hanging from its branches or twining themselves so close against the bark that they often seem as if sculptured on its trunk; or paused to listen to the quick rustle of the wind in palm-leaves fifty feet above our heads, not at all like the slow, gathering rush of the wind in pine-trees at home, but like rapidly running water. Through the narrow path an immense butterfly, of that vivid blue which excites our wonder in collections of Brazilian insects, came sailing towards us. He alighted in our immediate neighborhood, folding all his azure glories out of sight, and looking, when still, like a great brown moth, spotted with white. We crept softly nearer, but the first leaf trodden under foot warned him, and he was off again, dazzling us with the beauty of his wonderful coloring as he opened his wings and, bidding us a gay good-by, vanished among the trees. The sailing motion of these Morphos, though rapid, contrasts strikingly with the more fluttering flight of the Heliconians. The former give broad, strong strokes with their wide wings, the latter beat the air with quick, impatient, tremulous movements.