Simon Goodenough, 1500 Fascinating Facts, Londres, Octopus Books, 1983, p. 79.
The caddis fly lays its eggs near fresh water and the caddis larvae live in the water until they mature. In order to protect themselves, they build around their body a house of pebbles and bits of shell. They glue it together with a silky liquid fromtheir body. Some carry this house around with them.