25-27. SCYLLA ... CHARYBDIN. Ovid gives similar descriptions of Scylla at Am III xii 21-22 and EP III i 122, of Charybdis at Am II xvi 25-26, and of Scylla and Charybdis at Her XII 123-26 and Met XIII 730-33. All such descriptions in Latin poetry of course derive ultimately from Od XII 73-110.
25. QVOD LATRET AB INGVINE MONSTRIS. Professor R. J. Tarrant points out to me Ovid's imitation here of Ecl VI 74-75 'Scyllam ... candida succinctam latrantibus inguina monstris'; the rates and nautae of Ovid's line 26 are in lines 76 and 77 of the Virgilian passage.
25. QVOD. 'Granted that'. Bömer at Met VII 705 claims that the only passage where this is the necessary meaning of quod is Priapea VI 1 'quod sum ligneus ... Priapus ... prendam te tamen', but it seems to be the meaning required at Lucretius II 532-35 'nam quod rara uides magis esse animalia quaedam / fecundamque minus naturam cernis in illis, / at regione locoque alio terrisque remotis / multa licet genere esse in eo numerumque repleri'.
All six instances of the idiom cited by the OLD (quod 6c) are from poetry. In the two instances already cited, quod is followed by the indicative, as is the case at Prop III ii 11-16. Quod in this sense followed by the subjunctive seems to be an Ovidian idiom; it is used by him at Her IV 157-61 'quod mihi sit genitor, qui possidet aequora, Minos, / quod ueniant proaui fulmina torta manu, / quod sit auus radiis frontem uallatus acutis, / purpureo tepidum qui mouet axe diem— / nobilitas sub amore iacet!' and Met VII 704-7 'liceat mihi uera referre / pace deae: quod sit roseo spectabilis ore, / quod teneat lucis, teneat confinia noctis, / nectareis quod alatur aquis, ego Procrin amabam', and by an imitator of Ovid at Her XVIII 41.
26. HENIOCHAE NAVTIS PLVS NOCVERE RATES. The Heniochi lived on the eastern shore of the Euxine and were, as Ovid indicates, known as pirates (Strabo XI 2 12-13).
27. INFESTIS ... ACHAEIS. Mela includes the Achaei and the Heniochi in his list of 'ferae incultaeque gentes uasto mari adsidentes' (I 110). The two nations are grouped together by Strabo (XII 2 12) and Pliny (NH VI 30).
28. EPOTVM ... VOMAT. Professor R. J. Tarrant cites the verbal similarity at (pseudo-Ovidian) Am III v 18 'iterum pasto pascitur ante cibo'.
28. EPOTVM B ET POTVM C EPOTET MFHILT. Epotet is supported by Her XII 125 'quaeque uomit totidem fluctus totidemque resorbet' and Od XII 105-6 'τρὶς μὲν γάρ τ' ἀνίησιν ἐπ' ἤματι, τρὶς δ' ἀναροιβδεῖ / δεινόν'. Professor A. Dalzell points out in particular 'τρὶς ... τρὶς' paralleling ter ... ter in the present passage. But at RA 740 Ovid wrote 'hic uomit epotas [uarr et potat; hic potat; optatas; acceptas; aequoreas] dira Charybdis aquas'; and the corruption to epotet seems much more probable than the inverse. Ovid elsewhere uses only the perfect participle of epotare.
29. LICENTIVS ERRANT. Ovid is clearly imitating Aen VII 557-58 (Juno to Allecto) 'te super aetherias errare licentius auras / haud pater ille uelit, summi regnator Olympi', apparently the only other instance of licentius in classical verse.
31-32 act as a bridge to the next major section of the poem, and do not in themselves contribute to what has been said.