Thanks, Oakwoman. I got that same list for butterfly yarn but most of it looked like cotton yarns, nothing particularly 'novelty-ish' though a few further down the list looked similar to ladder yarns and some looked like eyelash yarns. I wonder what the OP is referring to.
By butterfly yarn I mean the kind that has a thick section and then thins out. I seen it on Yarn Paradise site. Similar to ladder.