(i) Twisted or Contorted : If one margin of the appendage overlaps that of the next one and so on as in china rose ladys finger and cotton it is called twisted.
(ii) Imbricate :
Out of the five petals one is completely external, one completely internal and in each of the remaining three, one margin is internal and the other is external. It is subdivided into four sub parts
- Simple Imbricate : When one petal is completely overlapped by other and one is completely overlapping to other and rest three arranged in twisted manner.
- Descending imbricate or Vexillary : In pea and bean flowers, thre are five petals, the anterior petal is innermost and the posterior petal is the outermost and largest (standard) which overlaps the two lateral petals (wings) which in turn overlap the two smallest anterior petals (keel); this type of aestivation is known as vexillary or papilionaceous.
- Ascending Imbricate :
The posterior petal is innermost, i.e., it s both margins are overlapped e.g. Cassia and Bauhinia.
- Quincunicial :
It is modification of imbricate type. Out of the five petals, two are completely internal, two completely external and in the remaining petal one margin is intenal and the other margin is external; eg: Murraya.
