Anonyme « Phryganea », Random Notes on Natural History, Providence, R. I., Southwick & Jencks, vol. II, n° X, 1885, p. 78.
The old english world Cadas means a case for security. The word still lingers in tea-caddy. The case-worm or larva of Phrygane is a soft-bodied creature, but it has a firm head and strong jaw. It is supplied with six legs, well adapted for locomotion, and with two hooks at the end of the tail by which it secures itself in its case. It is a rapacious and pugnacious insect. It feeds upon fresh-water mollusks, larvae, polyps etc. As a builder it makes use of the materials at hand.
The old Free Masons many have taken a lesson from it, and longfellow might have had it in mind when he sang,-
« That is best which lleth nearest
Shape from that thywork of art »
Sometimes the case is made of sticks, sometimes of grains of sand and in Great Britain, sometimes of the shells of the small river-snails (Planorbis), even while their proper owners have them in occupation. The cases not only serve for protection but for anchorage also, and they are found to be heaviest where the current is strongest- the creature having added materials to increase the weight.
If the caddis be deprived of his case, it will at onces set to work to construct another ; and, in confinement, it will build of materials supplied to it, such as small fragments of glass and coral and the broken teeth of combs. However rough the outside of the case may be, the inside is perfectly smooth, for it is lined with the same cement which binds the materials together and which is exuded from the mouth of the creature.
It is interesting to watch the caddis shifting his ground, moving his habitation from one part of the river-bed to another. So much of the body as will allow the legs free motion is protruded, and the creature strains like a horse with a heavy load, whilst its dwelling moves forward more or leas steadily according as it presents a smooth or roughened surface.
Before the pupa change take place the caddis draws itself entirely into its snug quarters, and spins a strong netted covering over the entrance to the case. Having thus « barred the door » against intrusion, it dozes off into the long sleep, the waking from which shall be an introduction to a new life, in another element.
The Phryganidae in their perfect state differ from others of the Neuroptera, in that they are coveed with minute hairs. Hence Westwood and other English naturalist have classed them as a separete order, the Trichoptera or hairy winged insects.
In dress the Phryganea are a sober people –browns, drabs and yellows are their favorite colors. Cross-venations give their wings a netted appearance. Their antennae are long- in some instances very long, and the wings are carried longitudinaly.