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This is a smaller variety of water caltrop (Trapa natans), possessing only two horns, and it is abundantly produced in the area around Linping Lake. Those originating from Jiaxing are named "Huntun Qing" (Wonton Green) due to their resemblance to wontons; compared to other water caltrops, they are smaller in size but sweeter in taste. "Shajiao" (Sand Horn) is even smaller than "Huntun Ling," with a reddish color and an exceptionally sweet flavor.

Its taste is sweet and its nature is neutral; it greatly tonifies Spleen Earth Qi without causing Qi stagnation. "Huntun Qing" has a cold nature; when eaten raw, it resolves accumulated summer-heat and irritability, generating body fluids; when cooked, it strengthens the Spleen, harmonizes the Stomach, and benefits Qi.

(The book *Huajing* states: The late-maturing and plump-sweet variety is named "Huntun Ling." The *Yaoxing Kao* [Examination of Medicinal Properties] states: Both "Huntun" and "Shajiao" can be consumed raw or cooked; when mature, they are sweet and fragrant, tonifying the Middle Jiao and benefiting Qi.)

(Black Olive Kernel) originates from Guangdong. It is now commonly sold in fruit shops; its skin is yellowish-black, the flesh is white, and the texture features layered patterns resembling that of Sepia (Cuttlebone). It is served as a vegetable or fruit dish during banquets.

The *Jijie* (Collected Explanations) section of the *Bencao Gangmu* [Compendium of Materia Medica] states: Black olives are dark greenish-black, with soft and sweet flesh. When the flesh is taken, pounded, and dried, a white frost naturally forms like salt, known as "Olive Paste." Its kernels are large and fat, named "Lanren" (Olive Kernel). However, the therapeutic indications recorded therein all refer to "White Olives," which are the "Qingguo" (Green Fruit) commonly eaten today. Furthermore, the record stating that olive kernels treat dry lips refers to the kernel within the seed of the Qingguo, not to the Black Olive Kernel. This omission is now supplemented by records from Lingnan fruit catalogs. According to the *Muyu* [Talks on Trees] section of the *Yuezhi* [Records of Yue]: There are two types of olives: green and black. People in Fujian call the white ones "Qingguo," whereas in Guangdong, they are only called "Bailan" (White Olive), not "Qingguo." White olives have mild efficacy, so people rarely cultivate them. Black olives are cultivated in various townships under Panyu. Two years after planting, the saplings grow to eight or nine chi in height; grafting is required for them to bear fruit. A small harvest occurs in the third year, and a large harvest in the tenth year. The tree trunk is tall and straight, mostly single-stemmed, branching out only at the top. There are male and female trees; the male serves as the main stock, and the female as the scion, analogous to a wife joining her husband's family. The fruit is about the size of a date, approximately one cun long, smooth without ridges or lobes. Fruits formed first hang downwards, while those formed later face upwards. They ripen in the eighth and ninth lunar months and are harvested using long poles from ladders. Alternatively, incisions about one cun deep are made on the east side of the trunk, filled with red salt, causing fruits on that side to drop; the same applies to the west, north, or south sides. This corresponds to the ancient poetic line: "Numerous green fruits fall upon red salt." Black olive seeds are large with thick flesh; their nature is warm, resulting in a taste that is astringent yet sweet. Soak them in warm water until soft; once the purple oil floats up and overflows, they are ready to eat. If the water is too cold, gum-like substances form; if too hot, the flesh becomes tough. Therefore, warm water must be used to harmonize and mellow their nature, embodying a principle of gentle admonition. Summarizing both types: White olives are male, black olives are female; white belongs to Yang, black to Yin. Yang thus manifests as white color and promotes Qi movement; Yin thus manifests as red/dark color and nourishes Blood. Because black is Yin, it possesses edible kernels; because white is Yang, its kernels are small and undeveloped. This is their distinction.

The kernel tastes sweet and bland; it moistens the Lungs, directs Qi downward, nourishes Blood, and detoxifies various fish poisons.