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The leaves of *Poncirus trifoliata* (Zhicheng) have two notches. The leaves of *Citrus reticulata* (Ju, Tangerine) are pointed at both ends and lack these two notches. The leaves of *Citrus maxima* (Gan, Pomelo) are similar to those of tangerine, but the pomelo tree is uniquely thornless, whereas tangerine, trifoliate orange, and sweet orange all have thorns.

The peel of tangerine has fine texture, is red and thin, contains many fibrous membranes internally, and tastes bitter and acrid. The peel of pomelo (*Citrus maxima*) has coarse texture, is yellow and thick, contains much white pith/membrane internally, and tastes acrid and sweet.

The peel of citron (*Citrus medica*) is the thickest, with even coarser veins, yellow in color, containing many membranes but no fibers internally, and tastes predominantly sweet with little acridity. One can distinguish them accurately by these characteristics. Tangerine peel is warm in nature, while pomelo peel is cold. Currently, market tangerine peels are often adulterated with pomelo peel. Pomelo peel is still usable, but pomelo peel differs significantly from tangerine peel.

(Pomelo peel) tastes bitter and acrid, has strong aroma and flavor, can ascend and descend, belongs to Yin within Yang, enters the Qi aspect of the Spleen and Lung meridians, as well as the Foot-Yangming Stomach meridian. It opens the stomach and harmonizes the middle, promotes digestion of water and grain, regulates dryness and dampness, relieves chest fullness and resolves phlegm, treats upper qi coughing, stabilizes vomiting, belching, and acid regurgitation, frequent spitting of clear fluid, large intestine obstruction, and qi-type dysentery. It removes lingering heat and retained water in the bladder, and treats alcohol-induced disorders.

Retaining the white pith tonifies the Spleen and Stomach because the pith possesses a sweet quality; removing the white pith regulates Lung Qi, eliminates phlegm, and drains Qi. The reason for removing the white pith is to prevent the sweet nature from moderating the acrid dispersing action.

Tangerine flowers in summer and fruits in autumn, receiving less Fire Qi and more Metal Qi. (Chen Zhongchun notes:) When combined with tonifying herbs, it acts as a tonic; when combined with purgative herbs, it acts as a purgative.

[Fragmented text follows, likely referring to specific preparations or contraindications involving interactions with Zhi Shi, intestinal blood, cold injury, food stagnation, etc., which are too fragmented to translate fully accurately without reconstruction.] ...thick and sticky powder. Take each with Almond seeds... mix into pills. Combined with Coptis Rhizoma and pig bile.

[Discussion] Tangerine peel tastes bitter and acrid, with balanced bitter and acrid properties and warm temperature. Based on its bitter-draining, acrid-dispersing, and warming-moving actions, it serves as an agent for moving stagnant Qi. Like other Qi-dispersing herbs, if used without indication, or if single-used and abused over long periods, it can consume true Qi. Those with deficient Middle Qi and Qi failing to return to its root should avoid using it with Qi-consuming herbs. Vomiting due to Stomach deficiency with fire should not be treated with warm, hot, aromatic, and drying herbs.

[Processing] For formulas that harmonize the middle and regulate the Stomach, retain the white pith. For formulas that direct Qi downward and resolve phlegm, remove the white pith. To remove the white pith, wash and soak in salt water, scrape off the fibrous membranes, and dry.