Arrangement of whorls

Arrangement of whorls

The position of perianth (sepals, petals, tepals) parts relative to one another is called perianth arrangement.

1          Cyclic or whorled: All the floral parts are arranged in definite whorls. Example: Brassica,Solanum.

2          Acyclic or spiral: The floral parts are arranged in spirals on the elongated fleshy torus. Example: Magnolia.

3          Spirocyclic or hemicyclic: Some parts are in whorls and others parts are in spirals. Example: Nymphaea, Annona, Polyalthia