In addition to the ordinary (ordinarium, ordo) and canon of the mass (canon missæ),1 the missal (missale, liber missalis) contains the propers for the liturgical year. Including the sung portions, sometimes with notation, these consist of the office (officium, or introitus), psalm, collect (oratio), epistle (epistola), gradual (graduale) with verse, alleluia with verse, tract (tractus, used at certain seasons only, such as Embertide2), sequence (sequentia), gospel (evangelium), offertory (offertorium), secret (oratio secreta, or secretum), communion (communio), postcommunion (postcommunio), and (during Lent), the oratio super populum.3 Noted missals, such as Lbl Additional 39675, Ouc 78A and WOc F. 161 described in this chapter, contain musical portions with neumes (square, rectangular or lozenge-shaped note symbols representing pitches) on fourline red staves for certain parts set to melodic plainchant.4 There was also provision for special services, such as suffrages (suffragia communia), votives (missæ votivæ, such as those in honour

1 The arrangement of the ordinary is discussed by Hughes, Medieval Manuscripts for Mass and Office (repr. 1995), ch. 7, 148-53 sections 738-41.