Some say the lark and loathed toad change eyes,
O, now I would they had changed voices too,
Since arm from arm that voice doth us affray . . . .
Juliet refers the folkore idea that because the ugly toad has beautiful eyes and the beautiful lark has ugly eyes, the two must have exchanged eyes. Now she says that the toad and the lark should have exchanged voices, too, since the song of the lark tells them the ugly truth that Romeo must now leave.