What is recorded in Hanshu Yiwenzhi?

The appearance of "special spectrum" describing a certain class or animal or plant is one of the signs of biological development in this period. There are 38 volumes of fragrant animals recorded in Hanshu Yiwenzhi. This shows that at the latest in the Western Han Dynasty, there has been a spectrum dedicated to livestock. Later, Sui Shu Jingji Records recorded many animal monographs, such as Xiang Ma Jing, Xiang Niu Jing, Xiang Duck Jing, Xiang Goose Jing, Xiang Chicken Jing, Pig Raising Law, Sheep Raising Law and Tao Zhugong Fish Raising Law. In terms of plants, Sui Shu Jingji Zhi recorded various records, such as bamboo score, Zhilue and Zhijing. According to Sui Shu, these books still exist in the Liang Dynasty. Later, most of them were lost except bamboo scores.