William J. Claxton, Stories of insect life, Londres, Blackie ans son Limited, 1912, p. 40.

Lying down on the bed of the pond or stream we may see something which looks like a little piece of stick. Take it up and examine it carefully, and you will prabably find a fat little grub inside- the caddis grub. This creature cleverly disguises itself by making a little case resembling some dry twig, and only protruding its head in search of food. And well is it that the caddis grub adopts this disguise, for there are many fierce and hungry pond creatures which would soon snap it up if they saw it.