Pappus (botany) Pappus (botany) The pappus is the modified calyx, the part of an individual floret, that surrounds the base of the corolla tube in flower heads of the plant family Asteraceae. The term is sometimes used in other plant families such as Asclepiadaceae (milkweeds), whose seeds have a similar structure attached, although it is not related to the calyx of the flower. The Asteraceae pappus may be composed of bristles (sometimes feathery), awns, scales, or may be absent. In some species, the pappus is too small to see without magnification. In species such as Dandelion or "Eupatorium", feathery bristles of the
Form (botany) Form (botany) In botanical nomenclature, a form ("forma", plural "formae") is one of the "secondary" taxonomic ranks, below that of variety, which in turn is below that of species; it is an infraspecific taxon. If more than three ranks are listed in describing a taxon, the "classification" is being specified, but only three parts make up the "name" of the taxon: a genus name, a specific epithet, and an infraspecific epithet. The abbreviation "f." or the full "forma" should be put before the infraspecific epithet to indicate the rank. It is not italicised. For example: A form usually designates a