1. Pericarpium Citri Tangerinae, the name of traditional Chinese medicine, is the peel of dry young fruit or immature fruit of Rutaceae citrus and its cultivated varieties. May to June series. Young fruit, dried, commonly known as "green husk"; Harvest immature fruits in July and August, divide them into four petals from peel to base, and remove all petals. Sun-dried, commonly known as "Four Flowers Green Peel". 2. Four-flower green tangerine peel: the peel is divided into four petals, rectangular, with a length of 4~ 150px and a thickness of 0. 1~5px. The appearance is grayish green or dark green. The thickest and oiliest room; The inner surface is white or yellow-white, rough, with yellow-white or yellow-brown small ribs. Slightly hard, easily broken, out of section. There are 1~2 rows of marginal oil chambers. It is fragrant, bitter and spicy.