[f. CASE sb.2 + WORM sb.] A caddis-worm; see CADDIS2. Hence, case-worm fly = caddis-fly, phryganea.

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1606.  S. Gardiner, Angling, 95. The case-worme, the dewe-worme, the gentile.

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1681.  Chetham, Angler’s Vade-m., iv. § 11 (1689), 40. Cod-bait, Cadis-worm, Cad-bait, or Case-worm … Are all one and the same Bait.

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1826.  Kirby & Sp., Entomol. (1828), II. xxiii. 300. Those caseworm-flies that are remarkable for their long antennæ.

4

1836–9.  Todd, Cycl., II. 865/1.

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