A Crow caught in a snare prayed to Apollo to release him, making a vow to offer some frankincense at his shrine. Being rescued from his danger, he forgot his promise. Shortly afterwards, on being again caught in a second snare, passing by Apollo he made the same promise to offer frankincense to Mercury, when he appeared, and said to him, "O thou most base fellow! how can I believe thee, who hast disowned and wronged thy former patron?"