rock-roller n
1 = caseworm n. West, chiefly UT Cf rock bait n, rock worm n 1
1892 Heber Herald (UT) [20 June 3]/2, F[i]shing silver-sides or chubs is now taking up the greater part of the boys’ time, they take a thread line and pin hook, and bait with rock rollers or angle-worms. 1913 Paul–Barnes Forest Groves 203 UT, Caddis Flies.—Have you ever turned over the flat rocks in the bed of swift-flowing canyon streams? If so, you must have noticed, in summer, that to these rocks often cling many small tubes sometimes an inch long, composed of sand, or of small pebbles, or of small sticks cemented or glued together. Fishermen call them rock rollers, and use the insect that is inside the case as a trout bait. 1934 Salt Lake Telegram (UT) 9 May 19/4, The caddis fly or rock roller is a cream colored worm with a black head. It is found near the rocks and in a case made of bits of wood or stone which they form with the aid of a sticky secretion of their mouths. 1958 Salt Lake Tribune (UT) 8 June sec C 9/3, [Advt:] Live Bait— . . Rock Rollers. 1965 DARE (Qu. R3, Whitish, worm-like creatures, found in ponds, that hatch into dobsonflies, and are commonly used for fish bait; total Infs questioned, 75) Inf UT3, Rock-rollers. 1978 Zwinger Wind 28 seUT, The bottom of the pool is quilted with caddisfly larva trails—“rock rollers” in local idiom. 1999 DARE File WY, [A friend], who grew up in Wyoming, referred to the larva of the helgramite as a “rockroller.” 2020 DARE File—Internet, It is rumored that I fly fished with flies tipped with a worm, until I was 12. In reality, they were ‘rock rollers’ which are caddis larvae. . . My father was a school teacher . . and therefore we were able to spend the summers fly fishing in Utah on the Green River, Blacksmith Fork, Logan, Provo and scores of other blue ribbon streams in Wyoming, Montana, and Idaho. I have been a Montana licensed guide since 1993.
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