Walruses, "mammals." Living in the ocean, it can also move on land. The body is large, dark brown or grayish yellow in color, no hair on the skin, small eyes, no pinna, and two particularly long teeth on the upper jaw, which can be used as a substitute for ivory. Feeds on baby sharks, squid and stingrays. (Hanyu Da Dictionary). Because of its huge size and long teeth, walruses are like elephants, so they are called elephants in the sea.
Elephants were widely distributed in ancient China, and elephants also existed in the Central Plains during the pre-Qin period. "Lü's Spring and Autumn": "Merchants serve elephants, in order to abuse Dongyi, Zhou Gong expelled them with teachers, as for Jiangnan." "As the climate gradually cooled, the elephant living area gradually moved south.
In ancient times, ivory was also often used to make objects, for example
Ivory cards, that is, letters made of ivory. Tooth cards, "ivory or bone horn notes." ”
Ivory wat board, wat board made of ivory, also called hand board. "Sui Shu Rites VII": "Descending from the Western Wei Dynasty, more than five pins, universal ivory, and more than six pins of bamboo." ”
Ivory radish, a craft carved from ivory in the Qing Dynasty.
Dawenkou culture ivory comb.
Ivory fish dart.
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Hemudu culture ivory dagger.