Robert Kemp Philip, That’s it or Plean Teaching an encyclopaedia of universal formation, New York, Dick & Fitzgerald, 1860, p. 367.
Caddis worms, 11, those curious and indescribable looking things, that moving about on the bottom of ponds and streams seem like insects entangled amid bits of chips, stone, shell, &c., are the larvae of another species of insect, having four hairy transparent wings. One sort house themselves in straws, called from thence straw worms; others in two or more sticks laid parallel to one another, creeping at the bottom of brooks; others with a small bundle of pieces of rushes, duck weeds, stick, &c., glued together, wherewith they float on the top, and can row themselves therein about the waters with the help of their feet; others in cases formed of fragments of stone and shells move slowly about the bottom of the waters which they inhabit.
It is a notable architectural faculty, which all the varieties of these creatures have together such bodies as are fittest for their purpose, and then to glued them together, some to be heavier than the water, that the animal may remain at the bottom, where its food is, and some to be lighter than water, to float on the top, and gather its food from thence. These little houses look coarse, and show no great artifice outwardly, but are well tunnelled, and made within with a hard tough paste; Into which the hind part of the worm is so fixed, that i can draw it cell after anywhere, without danger of leaving it behind; and can thrust forth or draw in its body, as may suit its wants.