Those are thorns of on skin of Silk Cotton Tree in Bengali “Shimul Gach”. This skin is from a dried skin of the tree.
Scientific name : Bombax ceiba Linn. Synonym : B. malabaricum Dc. Family : Bombacaceae.
Names : Shimul, Shimultula, Shimulgach (Bengla); Silk cotton tree Red silk cotca tree (English).
Taxonomical features : A tall deciduous tree with a straght trunk having a clear boce of 20-30 m with spreading branch (not so much). Stem : Bark grey or brown covered with black hard conical prickles. Leaf : Digitate, large spreading crowed at the ends of branches, leaflets 5-7 elliptic, lanceolate, ovate, lanceolate petiole 20 cm long. Flower : Bright red, numerous, crowed at the ends of branches, appeainay before the new leaves appearing deface the new leaves. Fruit : Capsules downy woody, ellicpsoid, 5-angled. Seed : Ovoid, smooth, black, or grey, numerous embedded its long white silkey cotton gum; light brown, and gradually becomes opaque and dark brown.
Flowering and fruiting period : February-March and April-May.
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