Bronze animal mask fittings for horse harnesses are seen as early as the late Shang and Western Zhou periods. Several of these are illustrated by Cheng Dong and Zhong Shao-yi, Ancient Chinese Weapons - A Collection of Pictures, Beijing, 1990, p. 38, pl. 2-81, a bovine mask, p. 41, pl. 2-94, a humanoid face, and p. 62, pls. 3-59 (a bovine mask) and 3-60 (a humanoid mask). All of these were meant to frighten and have more simplified shapes and are lacking the graceful lines of the present mask. The deep curving grooves that follow the contours of the mask can also be seen on a pair of bronze plaques of a tiger with its kulan prey, dated to the 6th – 5th century BC, in the collection of the Nelson-Atkins Gallery, Kansas City, illustrated by E. C. Bunker et al., “Animal Style” Art from East to West, The Asia Society, 1970, p. 115, pl. 84, where they are ascribed to Inner Mongolia. Curved grooves similar to those of the present mask accentuate the various areas of the tigers’ bodies, as well as their heads, in a manner very similar to that found on the mask. A pair of gold tiger plaques worked in the same groove-band style, was excavated from Ahluchaideng in Inner Mongolia, a site where mostly Warring States material was found, and is illustrated by Tian Guangjin and Guo Suxin in Ordos Bronzeware, Beijing, 1986, col. pl. 5. The shape of the eyes also appears similar. And the small heart-shaped ears are similar in shape to the tiny ear on a Liyu-style bird-shaped zun in the Freer Gallery of Art, illustrated by T. Lawton, Chinese Art of the Warring States Period, Washington, 1982, pp. 30-31, no. 3. The same tiny ear can be seen on a small bovine head from Fenshuiling, Changzhi Xian, Shanxi province, illustrated in Kaogu xuebao, 1974.2, pl. 5.3.