George P. Upton,
The Standard Operas: Their Plots…
“ He thinks of the mother whom he has never known, and of that mysterious being whom he has never seen, who should make the companionship he observes among the birds. The passion of love begins to assert itself vaguely and strangely, but full soon it will glow out with ardent flame. A bird flying over his head sings to him. He can understand its song and fancies it his mother's voice coming to him in the bird-notes. It tells him now he has the treasure, he should save the most beautiful of women and win her to himself. ”
