Lincolm Coles Pettit, Introductory Zoology, Saint Louis, The C.V. Mosby Company, 1962, p. 226.

Trichoptera, or caddis flies, are more common and more important than neuropterans and mecopterans, particularly as fish food in streams where the aquatic larva make strange and often complex tubes in which they grow. The tubes are in some cases transported by the caddis worms in crawling, but others are fastened to rocks.