Das sind eher die vom T-Shirt... zumindest entsprechen meine Bauchnabelfussel immer der Farbe des Shirts was ich trage.
Wikipedia: BauchnabelfusselManche sammeln ihre Fussel auch:
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Featuring the world's biggest collection of one person's
navel fluff (lint), as certified by Guinness World Records.
Some people gaze into their navel for inspiration: I look into mine and see navel fluff. Also known as navel lint, it is that fascinating fluffy substance that forms mysteriously in the belly buttons of special people.
http://www.feargod.net/fluff.html