These notes are the result of some work done a year or two ago on the Medicean MS. of Aeneas Tacticus1 (Cod. Mediceus Laurentianus, Plut. lv. 4, Saec. xi.) in preparation for an edition of that unduly neglected author which I hope will soon see the light. I should not have thought it worth while to publish them separately were it not for two papers, at once laborious and brilliant, read by Mr. A. C. Clark to the Oxford Philological Society on the text of Cicero′s speeches, in May, 1912, and February, 1913. The extreme plausibility with which the reader then explained numberless corruptions, transpositions, etc., in the text of Cicero, by reconstructing the length of line and pagination of the MSS. in their several degrees of descent, led me to think that it might be of some interest to publish the results at which I arrived by working on the same lines with a Greek author. In my case the problem has been a far simpler one, as I only had one MS. to deal with; but as I came to my own conclusions quite independently, before I knew that the method was being applied elsewhere, I give them for what they are worth, only too glad to find myself in such good company.