《论衡·卷十六·商虫篇》
蝗虫吃谷物，自然有它停止的时期，好比蚕吃桑叶，自然会有饱足的时候一样。
夫虫食谷，自有止期，犹蚕食桑，自有足时也。
Locusts eat corn, which naturally has a period when they stop, just as silkworms eat mulberry leaves, which naturally have a time when they are full.