Reference for Chullin 258:26

ר' שמעון בעלמא קאי דקאמר תנא קמא האבר מטמא משום אבר מן החי ואין מטמא משום אבר מן המת אלמא

For the first Tanna had stated: THE LIMB IS UNCLEAN AS A LIMB SEVERED FROM THE LIVING BODY BUT IS NOT UNCLEAN AS A LIMB SEVERED FROM A CORPSE, and this clearly shows that the law in general is that a limb<span class="x" onmousemove="('comment',' With no flesh at all upon it.');">¹⁴</span>

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