appendix to _De Præscriptionibus Hæreticorum_) and Philastrius make him appear immediately after Valentinus," &c. We must first examine these two points a little more closely in order to ascertain the value of such statements. With regard to the first (1st) of these points, we shall presently see that the mention of the name of Ptolemseus along with that of Heracleon throws no light upon the matter from any point of view, inasmuch as Tischendorf has as little authority for the date he assigns to the latter, and is in as complete ignorance concerning him, as in the case of Ptolemseus. It is amusing, moreover, that Tischendorf employs the very same argument, which sounds well although it means nothing, inversely to establish the date of Heracleon. Here, he argues: "Irenæus and Hippolytus name him (Ptolemæus) together with Heracleon;"(l) there, he reasons: "Irenæus names Heracleon together with Ptolemæus,"(2) &c. As neither the date assigned to the one nor to the other can stand alone, he tries to get them into something like an upright position by propping the one against the other, an expedient which, naturally, meets with little success. We shall in dealing with the case of Heracleon show how untenable is the argument from the mere order in which such names are mentioned by these writers; meantime we may simply say that Irenæus only once mentions the name of Heracleon in his works, and that the occasion on which he does so, and to which reference is here made, is merely an allusion to the Æons "of Ptolemseus himself, and of Heracleon, and all the rest who hold these views."(3) This phrase might have been used, exactly as it stands, with {207}