1. This Chapter does not cover: (a) Edible products (other than guts, bladders and stomachs of animals, whole and pieces thereof, and animal blood, liquid or dried); (b) Hides or skins (including furskins) other than goods of heading 05.05 and parings and similar waste of raw hides or skins of heading 05.11 (Chapter 41 or 43); (c) Animal textile materials, other than horsehair and horsehair waste (Section XI); or (d) Prepared knots or tufts for broom or brush making (heading 96.03). 2. For the purposes of heading 0501.00.00, the sorting of hair by length (provided the root ends and tip ends respectively are not arranged together) shall be deemed not to constitute working. 3. Throughout the Nomenclature, elephant, hippopotamus, walrus, narwhal and wild boar tusks, rhinoceros horns and the teeth of all animals are regarded as "ivory". 4. Throughout the Nomenclature, the expression "horsehair" means hair of the manes or tails of equine or bovine animals.