Clumps of dust. Please dust this room, and be sure to get the curly dirt that's gathered under the couch.
curly dirtand house moss; slut's wool
puffs of dirt and dust. How long has it been since you swept under this bed? There's a mountain of curly dirt under here! No one's been in this room for an age. Look at all the cobwebs and curly dirt. She was a terrible housekeeper. House moss collected in all the corners of her rooms.