Shen Collection, Middle Volume. Radical: Insect (chóng). Kangxi strokes: 14. Page 1086, Entry 14.
Pronounced xi.
Book of Rites (Erya), Interpretation of Fish: Rongyuan is known as xiyi (lizard).
Etymological Dictionary of Chinese Characters (Shuowen): When found in the grass it is called xiyi; when found on a wall it is called yanting (gecko).
Compendium of Materia Medica (Bencao): The small one with five colors and a bluish-green tail is called xiyi. The small one that climbs walls and is black in color is called yanting.
Dialects (Fangyan) by Yang Xiong: Regarding xiyi, in the regions of Qin, Jin, and Xixia it is called shou-gong (palace guardian); it is also called lu. In Nanyang it is called yanting. When found in marshes it is called xiyi, and in Southern Chu it is called sheyi (snake doctor), or sometimes rongyuan.
History of the Former Han (Qianhan), Biography of Dongfang Shuo: Emperor Wu placed a shou-gong in a bowl and ordered Shuo to guess what it was. Shuo said: I thought it might be a dragon, but it lacks horns; I thought it might be a snake, but it has feet. It moves with a fluttering, pulsing motion and is good at climbing walls; if it is not a shou-gong, it must be a xiyi.
See the note under the character yan for further details.
Collected Rhymes (Jiyun): Also written as the variant forms ni and si.