Procne and Philomela as swallow and nightingale, or vice-versa?

CW

Sexual violence. Murder. Filicide. Cannibalism.

tl;dr

When and how did Procne become identified with the nightingale, Philomela with the swallow, in Greek poetry? When and how did this identification flip around in Latin poetry? What accounts for the switch?

Deets

Lines 568–569 of Hesiod's Works and Days read as follows:

τὸν δὲ μέτ᾽ ὀρθογόη Πανδιονὶς ὦρτο χελιδὼν
ἐς φάος ἀνθρώποις, ἔαρος νέον ἱσταμένοιο.

_{Hesiod. fl. c. 800 BCE. Ἔργα καὶ Ἡμέραι. ll. 568–569. Accessed at perseus.tufts.edu 1 January 2025.}

In Stanley Lombardo's translation:

Soon after, Pandion's keening daughter
The swallow appears, as Spring just begins.

_{Hesiod. fl. c. 800 BCE. Works and Days. Works and Days and Theogony. Trans. Stanley Lombardo. Intro. and Notes Robert Lamberton. Indianapolis: Hackett, 1993. pp. 23–60. ll. 630–631. p. 41.}

Robert Lamberton glosses these lines thus:

Pandion's keening daughter: Philomela, daughter of a legendary king of Athens named Pandion, was raped by her brother-in-law, Tereus. After cooking Tereus' son and serving him to his father for dinner, she and her sister Procne escaped, and as he was about to catch them, all three were turned into birds. Philomela, who was turned into a swallow, thus comes to stand for all swallows.

_{ibid., note to line 630 [568], p. 57. Emphasis added.}

This puzzled me. After all, Hesiod's original does not say "Philomela," just "Pandion's daughter," which could apply just as well to Procne as to Philomela. Furthermore, heretofore I had been under the impression that Procne had been turned into a swallow, Philomela into a nightingale, and Tereus into a hoopoe. (The English word "philomel" means "nightingale," as attested by Merriam-Webster.)

A look at Lombardo's own translation of Ovid's Metamorphoses seemed to confirm my prior understanding:

... poised on wings they were,
Philomela flying off to the woods
As a nightingale, and Procne as a swallow
Rising up to the eaves. And even now their breasts
Retain the marks of the slaughter, and their feathers
Are stained with blood. Tereus' desire for vengeance,
And his grief, made him swift, and he himself
Was changed into a bird, with a crest on his head
And an outsize beak instead of a sword.
He is the hoopoe, a bird that seems to be armed.

_{Ovid (Publius Ovidius Naso). Metamorphoses. 8 CE. Trans. Stanley Lombardo. Intro. W R Johnson. Indianapolis: Hackett, 2010. Book VI, ll. 771–780, p. 169. Emphasis added.}

Trying to account for the discrepancy between this and Lamberton's note, I turned to Ovid's Latin:

pendebant pennis. Quarum petit altera silvas,
altera tecta subit; neque adhuc de pectore caedis
excessere notae, signataque sanguine pluma est.
Ille dolore suo poenaeque cupidine velox
vertitur in volucrem, cui stant in vertice cristae;
prominet inmodicum pro longa cuspide rostrum:
nomen epops volucri, facies armata videtur.

_{Ovid (Publius Ovidius Naso). Metamorphoses. 8 CE. Book VI, ll. 667–674. Emphasis added. Accessed at perseus.tufts.edu 1 January 2025.}

As far as I can tell with my rusty Latin, the emboldened portion of the quotation immediately above means something like "Of whom, the one seeks the woods, the other comes to the rooves." I.e., pace Lombardo's translation, Ovid does not appear to specify which sister becomes which bird. A glance at a different translation, by A D Melville, confirms this:

They float on wings! One daughter seeks the woods,
One rises to the roof; and even now
The marks of murder show upon a breast
And feathers carry still the stamp of blood.
And he, grief-spurred, swift-swooping for revenge,
Is changed into a bird that bears a crest,
With, for a sword, a long fantastic bill—
A hoopoe, every inch a fighter still.

_{Ovid (Publius Ovidius Naso). Metamorphoses. 8 CE. Trans. A D Melville. Intro. and Notes E J Kenney. 1986. Oxford, England: OUP, 1987, reprint 1988. Book VI, ll. 668–675. Emphasis added.}

E J Kenney's gloss to the emboldened lines turned out to be enlightening:

the woods ... the roof: generally Greek poets made Procne the nightingale, Philomela the swallow; in Roman poets it is usually the other way about. See Introd. xxviii–xxix.

_{ibid., note to Book VI, ll. 668–9, p. 413.}

The relevant portion of the cross referenced pages of the introduction state:

By failing to specify which sister became which bird in the story of Procne and Philomela Ovid showed, without ostentation of pedantry, that he was aware that his predecessors differed on the point (vi. 668–9 n.).

_{ibid., Introduction, p. xxviii.}

Hesiod at the beginning of the glory days of classical poetry and Ovid at their end are both careful not to identify either Procne or Philomela definitively with the swallow, and by extension the other with the nightingale. Their original texts say only that one of the sisters is the swallow, the other the nightingale. So: which representative Greek poets identified Philomela with the swallow and Procne with the nightingale? Conversely, which representative Latin poets flipped this identification around? Is there any accepted explanation for when and why this switch occurred? I am not asking for a comprehensive account of these identifications, merely for an overview of the history with some examples.

Supplementary tags

hesiod works-and-days ovid metamorphoses translation intertextuality