Prose departure?

Why does Venture claim "Ladies, I take this leave in prose, / You shall see me next in other feet" when his speech is in (admittedly highly irregular) verse? Is he being shown as a liar with his language use? Or should this speech be set as prose (it's verse in my edition) and did the compositor of the 1637 quarto (the copy-text for my edition) decide to expand the speech slightly for the purposes of casting off properly?