乳草属植物的花蕾，俗称马利筋或花冠花。

wer buds of a plant from the genus Calotropis, commonly known as milkweed or crown flower. The plant is a hardy perennial native to South Asia and is often found in arid and semi-arid regions. It produces waxy flowers that can be white or lavender in color, with five pointed petals and a small crown-like structure. Calotropis has been used in traditional medicine systems for a variety of purposes, including treating skin diseases, inflammation, and as an antidote for snakebites. The plant contains a milky sap, which is a source of various chemical compounds, including cardiac glycosides.