Henry David Thoreau, Excursions, vol 5, Boston, Houghtonn Mifflin & Company, 1863.

Stretched over the brooks in the midst of the Frost-bound meadows, we may observe the submare cottages of the caddis-worms, the larvae of the Plicipennes; their small cylindrical cases built around themselves, composed of flags, sticks, grass, and withered leaves, shells, and pebbles, in form and color like the wrecks which strew the bottom, now whirling in tiny eddies and dashing down steep falls, or sweeping rapidly along with the current, or else swaying to and fro at the end of some grass-blade or root.