The utilization of local building materials

Ron TaylorPonds and streams, Londres, Concertina Publications, 1979, p. 32.

Caddis ‘worms’ build themselves cases from bits of fibre, sand grains and small stones, but this is probanly not so much an adaptation to fast-water life, as simply the utilization of local building materials. But many caddis worms do have large claws adapted for holding on, which, together with their heavy cases, stabilize them in flowing water.