Leverett White Brownell, Natural History with a camera, Boston, American Photographic Publishing Company, 1942, p. 108-109
There are many others forms of insect life tant one may find during a jaunt along a brook but possibly the most interesting is the little caddis fly. The flies themselves have very much the appearance of Male Dobson Fly small moths. Their wings, covered with silky hairs andscales, are usually soft brown or grayin color, and folded over their backs when at rest. They are sen in most abundance about ther margins of streams and swarming over the water at dusk, and are also attracted by light near the streams or ponds. The larvae are the most interesting, living in every brook and creeping over the bottom almost constantly. They build cases for themselves in which they spend their entire time during the larval stage. They hold themselves in these cases by hooks at the hind end of their bodies, but the fore parts of their bodies are extended from the case, allowing them to crawl about the bottom of the streams carrying it with them. When danger approaches they can quickly withdraw completely within the case, thus protecting themselves from their predatory enemies. These cases are built of small pieces leaves bits of sticks, small stones, grains of sand, or even minute
Water snails’ shells. These materials are fastened together by a viscous silk spun by the larvae. As the creature grows, it enlarges the case to fit its body or, occasionally, crawls put and builds a new one.