Passage 8.17.3
παρέχεται δὲ καὶ θαῦμα τοιόνδε ἡ Κυλλήνη· κόσσυφοι γὰρ οἱ ὄρνιθες ὁλόλευκοί εἰσιν ἐν αὐτῇ· οἱ δὲ ὑπὸ Βοιωτῶν καλούμενοι γένος ἄλλο πού τί εἰσιν ὀρνίθων, οὐκ ᾠδικόν. ἀετοὺς μὲν οὖν ὀνομαζομένους κυκνίας μάλιστα ἐοικότας κύκνῳ λευκότητα οἶδα ἐν Σιπύλῳ θεασάμενος περὶ λίμνην καλουμένην Ταντάλου· ὗς δὲ ἀγρίους λευκοὺς καὶ ἄρκτους τῶν Θρᾳκίων λευκὰς ἤδη που καὶ ἄνδρες ἐκτήσαντο ἰδιῶται·
Cyllene offers also the following marvel: there the birds called blackbirds are altogether white. Those which the Boeotians call by this name, however, are a different kind of bird entirely, not songbirds. I myself have seen near Sipylus, by the lake called Tantalus' lake, certain birds called swan-eagles, resembling swans especially in whiteness. Moreover, white wild boars and white bears from Thrace have already at times been kept by private individuals.