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Alisma (Zexie), grows in the ponds and marshes of Runan; it is now also found in Shandong, Heshan, and Jianghuai regions, with those from Hanzhong being considered the best. Sprouts emerge in spring, mostly growing in shallow water. The leaves resemble those of *Plantago asiatica* (Niushe Cao), with a single, long stem; white flowers bloom in autumn, growing in clusters, resembling *Eleocharis pellucida* (Gujing Cao). The roots are harvested in May, June, and August, and dried in the shade. Currently, people harvest them at the end of autumn and dry them in the sun. This herb is prone to rotting and insect damage and must be stored tightly sealed. Those from Hanzhong are large and long, with two forked tips at the tail end, which are considered the best. *Erya* refers to it as "Chang" (yang zhu qie), also known as "Xi" (same as Xi, si xi qie). *Suwen* states: "Body heat, flaccidity, sweating profusely like bathing, aversion to wind, and shortness of breath are called Jiufeng (Wind caused by alcohol)." It is treated with Alisma (Zexie) and Atractylodes macrocephala Rhizome (Baizhu), each ten parts, and Elsholtzia splendens Herba (Mixian) five parts, mixed and taken in an amount pinched between two fingers, administered after meals. "After meals" means taking the medicine before eating rice. Zhang Zhongjing treats miscellaneous diseases where fluid retention accumulates under the heart (Zhiyin), causing distressing dizziness, using Zexie Tang (Alisma Decoction). Alisma (Zexie) five liang, Atractylodes macrocephala Rhizome (Baizhu) two liang, two sheng of water, decocted to obtain half a sheng, divided into two warm doses. For treating Shanghan (Cold Damage), there are Da Zexie Tang (Large Alisma Decoction) and Xiao Zexie Tang (Small Alisma Decoction), as well as Wuling San (Five-Ingredient Powder with Poria), all of which use Alisma (Zexie); its ability to promote urination and stop water retention is paramount. *Shenshi Fang* also uses Alisma (Zexie) and Atractylodes macrocephala Rhizome (Baizhu) for Zhiyin, but the decoction method differs slightly. First, boil the two herbs in two sheng of water to obtain one sheng. Then, boil Alisma (Zexie) separately in one sheng of water to obtain five he. Mix these two juices and divide into two doses. For severe cases with impending vertigo, administration will surely cure it. Immortal prescriptions also use only Alisma (Zexie), pounded and sifted into powder, mixed with water and taken in divided doses totaling six liang daily; after one hundred days, the body feels light, and long-term use enhances mobility.

Dioscorea opposita (Shuyu), grows in the valleys of Mount Songgao; it is now widely available, with those from Beidu and Siming being the best. Sprouts emerge in spring, creeping along fences; the stems are purple, leaves are green with three pointed angles, resembling *Ipomoea batatas* (Qianniu), but denser and glossier; small white flowers bloom in summer, similar to jujube flowers; fruits resembling bells form among the leaves in autumn. Roots are harvested in February and August, though currently people harvest them in winter and spring. Those scraped to reveal white flesh are superior; those that are green or black are inferior. They are dried in the sun. The processing method involves selecting thick roots, scraping off the yellow skin, soaking in water, adding a little powdered alum (Bai Fan) to the water, leaving overnight, then taking out, washing clean to remove slime, and baking dry. People near the capital cultivate it very successfully. In spring, take the heads of perennial roots, mix with yellow sand and cow dung to make beds for planting. When shoots emerge, use bamboo tips as supports, not exceeding one or two chi in height, irrigate frequently in summer. Edible in the same year, extremely plump and delicious. There is a variety in the south growing in mountains, with roots thin as fingers, extremely firm; when scraped and boiled in soup, they form solid chunks without disintegrating, tasting even more exquisite. It is said to be particularly beneficial to consume, surpassing cultivated varieties. Another variety from the Jianghu and Min regions has roots like ginger or taro with purple skin. Some are very large, weighing over a jin per piece; peeled, they are delicious whether boiled or stewed. However, their nature is colder than those from the north. Local people there call it simply "Shu" (sound like Shu), also referred to as "Mountain Shu". *Shan Hai Jing* states: "Looking north from Jing Mountain towards Shaoze, the grasses there are mostly 'Shu' (sound same as Shuyu)." Guo Pu annotates: "Roots resemble taro, edible." Currently, people in Jiangnan call it simply "Chu" (sound Chu), likely due to variations in pronunciation. Based on this annotation, Dioscorea opposita (Shuyu) and "Shu" are the same species. Varieties produced in the north and south...