¹ Citations of Nonius Marcellus, given with Mercier's page numbers, are taken from W.M. Lindsay's Teubner edition (Leipzig, 1903); all references are to the initial line of a lemma. Fragments of Republican drama are cited from the third edition of O. Ribbeck, Scaenicae Romanorum Poesis Fragmenta (Leipzig, 1897–8), sometimes with references to more recent editions of individual authors. This paper will be followed in a subsequent issue of this journal by a series of notes and conjectures proceeding from its conclusions, under the title ‘Some fragments of Republican drama from Nonius Marcellus' sources 26, 27 and 28’, to which I here occasionally refer as ‘Some fragments’. I am grateful to the Journal's referee and its editor for helpful suggestions on these papers. This research was supported by the Social Sciences and Humanities Research Council of Canada.