Tuogu (Pinyin: tuó gǔ) is a drum made of skin. Its sound is like a chirping. ; the sound of chirping. ("Tuo" is also known as "Chinese alligator", "Tuolong", "Pigpolong", and its skin can be covered with drums.)

Emperor Zhuanxu was one of the five emperors in ancient China (Huangdi, Diku, Tang Yao, Yushun, Zhuanxu), and was known as the emperor of water virtue in the north. Emperor Zhuanxu was benevolent, wise and wise. At that time, in the world, the Quartet was adored by virtue, and all birds and beasts were influenced by him. Influenced by his uncle Shaohao since childhood, he especially loves music. When he heard the sound of the wind from all directions passing over the earth, he felt very pleasant, so he made the eight flying dragons imitate the wind and chanted, and named it "Chengyun Song", which was specially used to commemorate the Yellow Emperor.

On another whim, he made the Chinese alligator an advocate of music. The Chinese alligator hums like a drum, and has thick scales on its back. It sleeps in the cave at the bottom of the pond all day long, and has always been unfamiliar with music. But after receiving the order, it did not dare to neglect, and immediately turned its heavy body to lie on its back, waving its thick tail to hit its bulging gray belly, and the sound it made was really loud. Influenced by Emperor Zhuanxu, the human world used the skin of the Chinese alligator to cover the drum. This kind of drum is very valuable, called Tu drum.