gordius

Gor"di*us, n. Etym: [NL. See Gordian, 1.] (Zoöl.) Defn: A genus of long, slender, nematoid worms, parasitic in insects until near maturity, when they leave the insect, and live in water, in which they deposit their eggs; -- called also hair eel, hairworm, and hair snake, from the absurd, but common and widely diffused, notion that they are metamorphosed horsehairs.

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