Thoreau writes in his journal:
Red-wings fly in flocks yet. Near the oak beyond Jarvis land, a yellow butterfly,—how hot! this meteor dancing through the air. Also see a scalloped-edge dark-colored butterfly resting on the trunk of a tree, where, both by its form and color, its wings being closed, it resembles a bit of bark, or rather a lichen. Evidently their forms and colors, especially of the under sides of their wings are designed to conceal them when at rest with their wings closed . . .