Glossary of plant morphology others may form a tight spiral, or whorl, around the flower stem. First, at the base, are those non-reproductive structures involved in protecting the flower when it is still a bud, the sepals, then are those parts that play a role in attracting pollinators and are typically coloured, the petals, which together with the sepals make up the perianth (perigon, perigonium). If the perianth is differentiated, the outer whorl of sepals forms the calyx, and the inner whorl of petals, the corolla. If the perianth is not differentiated into sepals and petals, they are collectively known as tepals. In some
Calyx (anatomy) Calyx (anatomy) Calyx is a term used in animal anatomy for some cuplike areas or structures. Latin, from "calyx" (from Ancient Greek "κάλυξ, "case of a bud, husk"). The spicules containing the basal portion of the upper tentacular part of the polyp of some soft corals (also called "calice"). A body part of the Entoprocta from which tentacles arise and the mouth and anus are located. The body disk that is covered with a leathery tegumen containing calcareous plates (in crinoids and ophiuroids the main part of the body where the viscera are located). Either a minor calyx in the