Leonard Robert Brightwell, The Pond People, Londres, W. Gardner, Darton, 1949,
Every part of the pond is favoured by some species, and the floor is the chosen haunt of the caddis worms. Know to all fishermen as a very « killing » bait a caddis worm, really the caterpillar stage of the caddis fly, is a very helpless creature which, being slow to avoid foes, protects its long soft body in a covering of sticks, shells, small stones, etc. Each species of caddis, and we have several dozen, favours some special material. If one of the stone case building sort is poked out of its tube and put in a jar of water, with plenty of coloured beads, it will use the new material with very ornamental effect.