Justin de Nicopolis (Néapolis) se rendit auprès de lui à Rome et écrivit à l'empereur une supplique en l'engageant à faire cesser la persécution contre les chrétiens. Gerson (Cerdon), autrement appelé Marcion et Marc parurent sous lui; ils étaient venus de Rome et soutenaient que Jésus-Christ n'est pas le fils de Dieu prédit par les prophètes, et qu'il n'ya pas eu de Résurrection. Sur les baptisés, ils disaient: « Au nom du Père paru, au nom de la vraie Mère, et au nom du Fils qui est descendu sur Dieu, » avec d'autres extravagances.(p. 107)
which can be roughly translated (I use French so rarely now living in America - only to reprimand my children because it sounds better):
Justin Nicopolis (Neapolis) went with him to Rome and wrote a petition to the emperor to commit to stop the persecution against Christians. Gerson (Cerdo), otherwise known as Marcion and Marc appeared to him. They had come to Rome and maintained that Jesus Christ is not the son of God foretold by the prophets, and that there was no Resurrection. On the baptized, they said: "In the name of the Father there appeared, in the name of the true Mother, and in the name of the Son who came down on God, with other extravagances.
The point of course is that most people will simply say - 'oh, Michael is a late writer and he doesn't know what he is reporting' but the reality is that there are just so many of these 'conflations' of Marcion and Mark (the Philosophumena, Gregory of Nazianzus etc.) that there has to be something more to it than this.
Hermann Ratschke clearly agreed with my theory. Why is it so difficult for people to accep that Irenaeus might not have been the most reliable witness? Not only was he a partisan, there is no reason to think that the 'five books' Against Heresies represents represent anything other than a highly-edited third century 'greatest hits' package of original 'lectures' from the second century (perhaps by Hippolytus or some other third century devotee). Photius already notes the differences between the 'raw' testimonials of Irenaeus and the collections. This is also witnessed by the differences that exist between Tertullian's Against the Valentinians (which is clearly more original) and the material that survives in Book One of Against the Heresies.
Marcion is without question a 'subform' of Mark (as von Harnack notes. I happen to support Hilgenfeld's assertion that it is a diminutive subform. But that isn't the point. The connection between Marcion and Mark is so strong, there can be only one answer - 'Marcion' is a remembrance of the true St. Mark of history.
