Anonyme, Voices of the Garden, The Woods, And The Fields: Or the Teachings of Nature as Seasons Change, Londres, T. Nelson and Sons, 1882, p. 302.

Some curious instances occur where these soft animals protect themselves by means of an artificial covering, thereby manifesting a curious instinct in providing for their defence.The caddis worm, or larva of the brown May-fly, which passes the first stage of its existence in shallow streams, collects round its body a covering of straws, sticks, and smal shells, which it works together so as to form a strong protecting sheath for its body.