Passage 8.17.4
λαγῲ δὲ καὶ ἔλαφοι, τὸ μὲν Λιβυκὸν θρέμμα οἱ λαγῴ εἰσιν οἱ λευκοί, ἐλάφους δὲ ἐν Ῥώμῃ λευκὰς εἶδόν τε καὶ ἰδὼν θαῦμα ἐποιησάμην, ὁπόθεν δὲ ἢ τῶν ἠπείρων οὖσαι ἢ νησιώτιδες ἐκομίσθησαν, οὐκ ἐπῆλθεν ἐρέσθαι μοι. τάδε μὲν ἡμῖν λελέχθω τῶν ἐν Κυλλήνῃ κοσσύφων ἕνεκα, ὡς μὴ τοῖς ῥηθεῖσιν ἐς τὴν χρόαν αὐτῶν ἀπιστοίη μηδείς·
There are also hares and deer, the white hares being animals native to Libya. White deer I myself saw in Rome, and upon seeing them I marveled; but from which mainland region or island they were brought, I did not inquire. These points I have mentioned on account of the blackbirds on Cyllene, so that no one should doubt the truth of what has been said concerning their color.