After all is said and done, the great value of Traube's discovery remains. It is positive that the enlargements in the manuscripts were made at the direction of the author himself. They present to the modern editor of the _De Divisione Naturae_ the fascinating task of distinguishing the different revisions, and of following the growth of the subject in Johannes' mind. The best way, I believe, would be to print on the left-hand page the enlarged form of the text, for that is the form in which the author wished his work to be known to posterity. On the right-hand page, the briefest form, the nearest approach to his original draft, might be given, with indication, in the critical apparatus, of the successive stages by which the final text was reached. Possibly further research may reveal _O_, or even the hand of Johannes himself. For the present, we at least have accessible--if the contents of the libraries of Reims and of Laon are accessible--the material for preparing a highly accurate and well-nigh unique edition of one of the masterpieces of medieval philosophy. FOOTNOTES: [1] In Abh. d. k. b. Akad. d. Wiss., philos.-philol. u. hist. Classe, Muenchen, XXVI (1912). [2] In Migne, _Patrologia Latina_, vol. 122 (1865). [3] I have confined my illustrations almost entirely to passages exhibited in the plates. I have notes of many other examples quite as pertinent, but do not include them here, believing that those presented amply prove my point. [4] For an example, see Plate I (fol. 273). In the last regular line of the page, after writing _caelestis essentiae particeps est_, the scribe first omitted the words _de die--caelestis essentiae particeps est_ (an exceedingly easy haplography) and then added them, with signs of reference, in the margin immediately below. As the error is one of sight and not of hearing, he must have had a text before him. [5] Plate II (fol. 231^{v}) contains a striking instance. After the citation of St. Basil, the author bethinks him of another possible interpretation of his words (_An aliud ex uerbis ipsius--intelligendum_) and sets it forth in the enlargement. It is not probable, I believe, that the author dictated this forthwith to the scribe. As the existence of _O_ has been proved, it is more natural to assume that the enlargement had already been inserted there. [6] E.g., fol. 59 (I have no photograph). The added _quodam_ in l.10 of fol. 231 (Plate II) is not by _I_. See below, note 10. _Ut arbitror_ in the right margin seems exactly the thing that an author tucks in when revising and qualifying his work. But see below p. 138. [7] Plate III contains a specimen (fol. 64). At first this hand looks like that of the text, but it is really different. The corrections are, I believe, by _r^{1}_ himself. They had been made in _O_, I infer, but at first were not observed by _r^{1}_. The heading _De agere et pati_ is by a hand of the thirteenth century or later (= _h_).