carphologia

Carphologia or lint picking behavior is a sign infavor of delirious state.The actions of delirious or semiconscious patients, as if they are searching for or grasping at imaginary objects, or picking at the bed-clothes or their own clotes. This is a grave symptom in cases of extreme exhaustion or approaching death. Also known as floccillation.
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picking of pieces of straw from mud/adobe walls

See floccillation