Anonyme, « The Caddis Folk », The Youth’s Companion an Illustrated Weekly Paper for Young people and the Family, Boston (MA), Perry Mason, vol. LXXXVII, 2 octobre 1913, p. 520.
Mother Nature often hides her richest treasures beneath our very feet. Do you see that peculiar worm that clings to a rockdown in the clear water? One day a little gauzy-winged creature called the caddis-fly crept out on a half-sunken log and deposited a score of green eggs beneath the loose bark.
In nine days the eggs became tiny green worms, that fell into the water, and befan immediately to build house for themselves out of tiny particles of sand, mica, quartz, or bits of stick. Piece by piece each made his house, and bound the material together with strands of fine silk. When the house was complete, only the head and short legs of the worm protruded. The caddis-worm lives thus for nine months ; then one day it changes into a fly, rises to the top of the water, spreads its wings and flies away, to live a few days in the upper air.
« Once », says a Companion contributor, « I took one of these worms, removed it from its case, and put it in a dish filled with water, in which there were a number of flakes of clear micas. It began to build and in a few day it was literally living in a « glass house ». I could see how it lived.
« On its sides were tiny hooks by which it held itself in the case. Insects of this kind do not have lings, nor ordinary gills, but they breathe with what are called tracheal gills, minute fringes like fern leaves along their sides. When my pet needed air. It would pump water into its case spread the fringes, and wave them about in the current, and then expel the water. It did that every half-minute. I fed it bits of vegetables chopped fine, and kept it for several months. One morning it was gone. I searched and found the delicate caddis-fly into which the wirm had changed.
« There are several kinds of caddis-flies, and each chooses a different kind of house material. In the streams of California one kind uses bits of copper pyrites, and when the house is done. It looks like a little nugget of gold. Another builds a house so much like shell that men of science spent a long time hunting for the water-snail that inhabited that peculiar horn-shaped shell!
« Why do you suppose the caddis-worm builds this rough, rocky house ? It is because trout are fond of caddis-worm, but they do not like the gravelly case in which the wormlives.Nature has somehow told the worm how to protect itself fromthe hungry trout. »