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Phryganea

wings, ge and silken

PHRYGANEA ,in natural history, a ge nus of insects of the order Neuroptera. Generic character: mouth with a horny short curved mandible ; feelers four ; three stemmata ; antenna setaceous, long er than the thorax ; wings equal, incum bent, the lower ones folded. There are nearly sixty species, in two divisions. A. Tail with two truncate bristles. B. Tail without bristles. The insects of this ge nus are seen in a summer's evening Boat ing in the air in large masses, and are ea gerly devoured by swallows. They re semble moths, particularly the division called Tinew ; but may readily he distin guished by their feelers, and also by the stemmata situated at the top of the head. The phryganem proceed from aquatic lar va of a lengthened shape, residing in tu. bular cases, which they form by aggluti nating various fragments of vegetable sub stances, &c. These tubular cases are lined within by a tissue of silken fibres, and are open at each extremity. The in. eluded larvx, when feeding, protrude the head and fore-parts of the body, creeping along the bottom of the waters they in habit, by means of six short and slender legs ; on the upper part of the back is a sort of prop, preventing the case, or tube, from slipping too far forwards during the time the animal is feeding. One of the

largest species is the P. grandis, (see Plate IV. Entomology, fig. 2.) This in sect is about an inch in length, very like a phalama ; the upper wings are grey, marked by various darker and lighter streaks and specks, and the under wings yellowish brown, and semitransparent. The larvx of this genus is known by the name of cadew-worm, and is frequently used by anglers as a bait. When arrived at full growth, it fastens the case or tube, by several silken filaments, to the stem of some water plant, or other convenient substance, in such a manner as to project a little above the surface of the water, and casting its skin, changes to a chrysa lis of a lengthened shape, and displaying the immature limbs of the future phryga nea, which in a fortnight emerges from its confinement. It inhabits Europe.