CORYDALIS (Neo-Lat.. from Gk. Kopycla2,71c, korydallis, Koprei6e, korydos, crested lark, from sopvc, korys, helmet) or HOBSON. A genus of large. net-veined insects (true Neuroptera). rep resenting the family Sialidm„and peculiar to Amer ica, where its larva. used for bait tinder the names 'crawler,' dobson."bell devil,' and many others, is the largest of our aquatic insects. The single species (Corydylis To•nata), often called '11M1 grammite,' is brownish-green in color. about two inches in length, and expands its four nearly equal wings fully six inches. "In the female the jaws are very large, flat, and toothed at the ex tremity, but in the male they are remarkably long and slender, not toothed, and the sharp tips crossing each other; their only use is evidently for seizing the soft, somewhat yielding body of the female during the act of pairing; hence, dur ing its short life the male, at least, takes no food." The female lays her eggs in midsummer, in white, chalky masses almost an inch wide, on tree-leaves, rocks, timbers, etc., overhanging water, into hvhich the young drop as soon as batched. These sink to the bottom and grow
rapidly into large, slate-gray, tough, predatory larva., which hide under stones, etc., in the rapid streams where they most abound. clinging firudy to some support with their anal hooks, while they seize in their jaws such living creatures as come within their reach. They remain in the water two years and eleven months, then creep out upon land, where they wander about at night for a few days, then pupate in sonic retreat and speedily emerge as adults. The larvae (dobsons) are regarded as the most satisfactory bait known for still-fishing, and are captured with nets, after overturning stones, etc., and frightening them out into the open water. For the many interest ing peculiarities of the structure and economy of this and other species of the Sialid;e (called 'adder-flies' in England), consult: Howard, The Insect Book (New York, 1901) ; Packard, Stan dard Xatund History, vol. ii. (Boston, 1884) ; Miall, The Yatural History of Aquatic Insects (London, 1895).