A hollow chamber

Anonyme, Pond Life, New York, Nature Program National Audubon Society, Doubleday, 1967, p. 19.

On the bottom of the pond or on the stems of water plants one can often see what looks like a small bundle of sticks moving awkwardly. If you look more closely at one end you may see a small head and the forelegs of the larva of the caddis fly. If you were yo break open the ticks you would find a hollow chamber in which the larva lives.

Without the home of sticks, which it glues together with a secretion from its own body, the wormlike larva would soon fall prey to fishes, newts and other predators. The caddis fly larva will also use small stones or snail shells to construct its home. Later, the larva will swim the surface and use its jaws to cut its way out to emerge as a mothlike fly.