This is mostly a question for the native speakers of English: How would you write apparatus (as in the app. criticus) in the plural in English? My Oxford Concise says nothing, the Wiktionary says it can be either -uses or the same as singular.
And by the way, anyone interested in textual criticism? I’m writing an article about indirect transmission of Vergil in the Saturnalia of Macrobius if there should be any person here interested in that.