气味甘、平，无毒。主漏下赤白，破症瘕 疟，五痔阴蚀，湿痹四肢重弱，小儿
囟不合。久服轻身不饥。
陈修园曰∶龟甲诸家俱说大补真水，为滋阴第一神品，而自余视之，亦不尽然。大抵介
虫属阴，皆能除热；生于水中，皆能利湿。其甲属金，皆能攻坚，此外亦无他长。《本经》
云∶主治漏下赤白者，以湿热为病；热胜于湿则漏下赤色，湿胜于热则漏下白色，龟甲专除
湿热故能治之。破症瘕者，其甲属金，金能攻坚也。 疟，老疟也，疟久不愈，湿热之邪痼
结阴分，唯龟甲能入阴分而攻之也。火结大肠则生五痔，湿浊下注则患阴蚀，肺合大肠，肾
主阴产，龟甲性寒以除其热，气平以消其湿也。脾主四肢，因湿成痹以致重弱，龟居水中，
性能胜湿，甲属甲胄，质主坚强，故能健其四肢也。小儿囟骨不合，肾虚之病；龟甲主骨，
故能合之也。久服轻身不饥者，言阴精充足之效也。
气味咸、平、微寒，无毒。主伤寒寒热，温疟洒洒，惊恚怒气，除拘缓，鼠 ，
女子带下赤白，久服强骨节，杀邪鬼，延年。（按∶补阴则生捣用，若 过则成灰，不能补
阴矣。方书注云∶ 用者皆取粉，外治之法。荒经者误收，遂相沿不改矣。）
陈修园曰∶牡蛎气平者，金气也，入手太阴肺经；微寒者，寒水之气也，入膀胱经；味
咸者，真水之味也，入足少阴肾经。此物得金水之性。凡病起于太阳，皆名曰伤寒；传入少
阳之经，则为寒热往来；其主之者，借其得秋金之气，以平木火之游行也。温疟者，但热
不寒之疟疾，为阳明经之热病；洒洒者，即阳明白虎证中背微寒恶寒之义，火欲发而不能径
达也
；主以牡蛎者，取其得金之气，以解炎暑之苛；白虎汤命名，亦同此意也。惊恚怒气，其主
在心，其发在肝；牡蛎气平，得金之用以制木。味咸，得水之用以济火也。拘者筋急，缓者
筋缓为肝之病。鼠 即瘰 之别名，为三焦胆经火郁之病，牡蛎之平以制风，寒以胜火，咸
以坚，所以咸主之。止带下赤白与强骨节二句，其义互见于龟板注中，不赘。杀鬼邪者，
补肺而申其清肃之威。能延年者，补肾而得其益精之效也。
[Gui Ban (Tortoise Shell)]
Flavor and Nature: Sweet, neutral, non-toxic. Indications: Leukorrhea with blood or white discharge (Lou Xia Chi Bai), breaking up masses and old malaria (Po Zheng Jia Nue), five types of hemorrhoids and genital erosion (Wu Zhi Yin Shi), damp-bi syndrome with heaviness and weakness in the four limbs (Shi Bi Si Zhi Zhong Ruo), failure of the fontanelle to close in infants (Xiao Er Xin Bu He). Long-term use results in a light body and reduced appetite (Jiu Fu Qing Shen Bu Ji).
Chen Xiuyuan stated: Various schools of thought claim that Gui Ban greatly tonifies True Water (Kidney Yin) and is the premier divine product for nourishing Yin. However, in my view, this is not entirely accurate. Generally speaking, creatures with shells belong to Yin and can all clear heat; those living in water can all promote diuresis and resolve dampness. Their shells belong to Metal and can all attack hardness and dissipate accumulations; there are no other significant merits. The *Shennong Bencao Jing* states: "Mainly treats leukorrhea with blood or white discharge." This is because the disease is caused by Damp-Heat. When Heat exceeds Dampness, the discharge is red; when Dampness exceeds Heat, the discharge is white. Gui Ban specifically eliminates Damp-Heat, thus it can treat this condition. To break up masses (Zheng Jia), it is because its shell belongs to Metal, and Metal nature is hard and can attack hardness. Old malaria refers to malaria that has persisted for a long time without healing; the pathogenic factor of Damp-Heat is firmly rooted in the Yin aspect. Only Gui Ban can enter the Yin aspect to attack it. Fire accumulating in the Large Intestine generates the five types of hemorrhoids; turbid Dampness flowing downward causes genital erosion. The Lung corresponds to the Large Intestine, and the Kidney governs the Yin organs. Gui Ban is cold in nature to eliminate Heat and neutral in Qi to dissipate Dampness. The Spleen governs the four limbs; due to Dampness forming Bi syndrome, heaviness and weakness result. Gui lives in water, so its nature can overcome Dampness. Its shell belongs to armor, and its substance is strong and firm, thus it can strengthen the four limbs. Failure of the infant's fontanelle to close is a disease of Kidney deficiency; Gui Ban governs bones, thus it can cause closure. Long-term use leading to a light body and reduced hunger describes the effect of sufficient Yin Essence.
[Mu Li (Oyster Shell)]
Flavor and Nature: Salty, neutral, slightly cold, non-toxic. Indications: Cold and fever from Shanghan (Taiyang Cold Damage), chills associated with warm malaria (Wen Nue Sa Sa), fright, resentment, and anger (Jing Hui Nu Qi), relieving spasms and flaccidity (Chu Ju Huan), scrofula (Shu Lou - lymphatic tuberculosis), leukorrhea with blood or white discharge in women (Nu Zi Dai Xia Chi Bai). Long-term use strengthens bone joints, expels evil spirits (Sha Xie Gui), and prolongs life. (Note: To tonify Yin, it should be used raw and crushed. If calcined into ash, it cannot tonify Yin anymore. Formulary notes state that what is used is powder, which is a method for external treatment. Absurd scholars mistakenly included it, and the error has been perpetuated.)
Chen Xiuyuan stated: Mu Li has a neutral Qi, which is Metal Qi, entering the Hand Taiyin Lung Meridian; it is slightly cold, which is Cold Water Qi, entering the Foot Taiyang Bladder Meridian; it tastes salty, which is the flavor of True Water, entering the Foot Shaoyin Kidney Meridian. This substance obtains the nature of Metal and Water. Any disease originating from the Taiyang meridian is named Shanghan; when it transmits to the Shaoyang meridian, it manifests as alternating cold and fever. Treating it involves borrowing its acquisition of Autumn Metal Qi to pacify the wandering of Wood and Fire. Warm malaria is a type of malaria characterized by heat without cold, belonging to Yangming meridian heat disease. "Sa Sa" refers to the meaning of slight back chills and aversion to cold in the Baihu Tang syndrome, indicating that Fire desires to emerge but cannot reach directly. Using Mu Li as the main treatment takes advantage of its Metal Qi to resolve the harshness of summer heat; the naming of Baihu Tang shares this same intent. Fright, resentment, and anger primarily reside in the Heart and manifest in the Liver. Mu Li's neutral Qi uses Metal to control Wood. Its salty taste uses Water to assist Fire (actually to subdue Fire). Spasm indicates tense sinews, and flaccidity indicates relaxed sinews; these are diseases of the Liver. Shu Lou is another name for Luoli (scrofula), a disease of Fire stagnation in the Sanjiao and Gallbladder meridians. Mu Li uses its neutrality to control Wind, its coldness to overcome Fire, and its salinity to solidify Yin; therefore, it is mainly treated with salty substances. The phrases regarding stopping leukorrhea and strengthening bone joints have their meanings interreferenced in the commentary on Gui Ban, so no further elaboration is needed. Expelling evil spirits refers to tonifying Lung Qi and asserting its clearing and descending authority. Prolonging life refers to tonifying the Kidney and obtaining the benefit of benefiting Essence.