Missal, this form was, with very few exceptions, reduced to antiphon-verse-doxology-antiphon. For example, the Tridentine Missal presents the Introit of the Fourth Sunday of Advent as follows: First the antiphon Rorate caeli from : Rorate, cæli, desuper, et nubes pluant iustum: aperiatur terra, et germinet Salvatorem. (Drop down dew, ye heavens, from above, and let the clouds rain the Just: let the earth be opened, and bud forth a Saviour.) Then the verse from the beginning of the psalm, : Caeli enarrant gloriam Dei et opera manuum eius annuntiat firmamentum (The heavens shew forth the glory of God, and the firmament declareth the work of his hands.) Then the doxology. Gloria Patri, et Filio, et Spiritui Sancto, Sicut erat in principio, et nunc, et semper, et in sæcula sæculorum. Amen. (Glory be to the Father, and to the Son, and to the Holy Ghost, as it was in the beginning, is now, and ever shall be, world without end. Amen.) Then, once again, the initial antiphon: Rorate ... Salvatorem. Introits, like Offertories and Communions, are believed to have evolved from simpler reciting tones. Introit melodies show this musical parentage most clearly, and are often anchored around two reciting notes which may be repeated or percussed. The melodies are mostly neumatic, dominated by neumes with two or three notes per syllable, although syllabic and melismatic passages also occur. The Introits of Old Roman chant share many similarities with their Gregorian cousins, and often include a repeated extra verse that fell out of use in the Gregorian repertory. Use of the incipit In the same way as Church documents are referred to by their incipit (their first words in Latin), Mass formulas are known by the incipit of their Introit, which is the first text in the formula. Thus a Mass for the dead is referred to a Requiem Mass, and the three Christmas Day Masses have been called Dominus dixit, Lux fulgebit and Puer natus. So too, Gaudete Sunday is a name for the third Sunday in Advent, Laetare Sunday for the fourth Sunday in Lent, and Quasimodo Sunday for the Octave or Second Sunday of Easter, because of the incipit of the Entrance antiphons of those Sundays. In Anglican liturgy In the Anglican Communion, Introit is the name given to the hymn or metrical psalm which is sung at the start of a service, a tradition which dates back to