Aristotle, De animalibus historiae, lib. I cap. IX (in the Leipsig edition of 1811, cap. VIII); Bekker page 491b:
Τὰ μὲν οὖν ἄλλα γένη πάντα τῶν ζῴων πλὴν τῶν ὀστρακοδέρμων καὶ εἴ τι ἄλλο ἀτελές, ἔχει ὀφθαλμούς· τὰ δὲ ζῳοτόκα πάντα πλὴν ἀσπάλακος. Τοῦτον δὲ τρόπον μέν τιν' ἔχειν ἂν θείη τις, ὅλως δ' οὐκ ἔχειν. Ὅλως μὲν γὰρ οὔθ' ὁρᾷ οὔτ' ἔχει εἰς τὸ φανερὸν δήλους ὀφθαλμούς· ἀφαιρεθέντος δὲ τοῦ δέρματος ἔχει τήν τε χώραν τῶν ὀμμάτων καὶ τῶν ὀφθαλμῶν τὰ μέλανα κατὰ τὸν τόπον καὶ τὴν χώραν τὴν φύσει τοῖς ὀφθαλμοῖς ὑπάρχουσαν ἐν τῷ ἐκτός, ὡς ἐν τῇ γενέσει πηρουμένων καὶ ἐπιφυομένου τοῦ δέρματος.
In the Latin translation after Scaliger:
Omnia igitur animantium genera oculis praedita sunt, praeter ea, quae testa operta sunt, et si quae alia imperfecta. Quae vero animal pariunt, eae omnes quoque, nisi talpa (aspalax). Verum hanc aliquo modo habere quis censere possit, omnino vero non habere. Omnino enim nihil videt, neque manifesto apparentes oculos habet. Detracta vero pellicula et oculorum sedem invenies, et nigritiem, quae secundum locum et spatium est a natura ipsis oculis attributa, perinde quasi inchoatos pellicula extrinsecus adnata occupauerit.
In Wentworth's translation:
All animals, as a general rule, are provided with eyes, excepting the ostracoderms and other imperfect creatures; at all events, all viviparous animals have eyes, with the exception of the mole. And yet one might assert that, though the mole has not eyes in the full sense, yet it has eyes in a kind of a way. For in point of absolute fact it cannot see, and has no eyes visible externally; but when the outer skin is removed, it is found to have the place where eyes are usually situated, and the black parts of the eyes rightly situated, and all the place that is usually devoted on the outside to eyes: showing that the parts are stunted in development, and the skin allowed to grow over.
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