This Marcianus is an otherwise unknown personage, unless we are to identify him, as Salmon suggests is possible, with Marcion. The suggestion is attractive, and the reference to Docetæ gives it a show of probability. But there are serious objections to be urged against it. In the first place, the form of the name, Μαρκιανός instead of Μαρκίων. The two names are by no means identical. Still, according to Harnack, we have more than once Μαρκιανοί and Μαρκιανισταί for Μαρκιωνισταί (see his Quellenkritik d. Gesch. d. Gnosticismus, p. 31 sqq.). But again, how can Marcion have used, or his name been in any way connected with, a Gospel of Peter? Finally, the impression left by this passage is that “Marcianus” was a man still living, or at any rate alive shortly before Serapion wrote, for the latter seems only recently to have learned what his doctrines were. He certainly cannot have been so ignorant of the teachings of the great “heresiarch” Marcion. We must, in fact, regard the identification as improbable.