續一切經音義 4.71

4.71

青蠅（下餘陵反考聲云飛蟲也鄭箋毛詩云蠅之為蟲污白色使黑喻佞人變亂善惡也又曰白珪之玷尚可磨也斯言之玷不可為也）。

Greenbottle flies (qingying 青蠅: the second character has the fanqie [reading] yu + ling [ying]. The Kaosheng states: "A flying insect." Zheng [Xuan's] commentary on the Mao Commentary on the Classic of Poetry states: "The fly, as an insect, defiles white color and turns it black, metaphorically representing how sycophants distort and throw into chaos good and evil." It also states: "A flaw in a white jade tablet can still be polished away; a flaw in these words can never be undone").