From December 18 to 23, III and IV class votive and Requiem Masses are prohibited.
No Gloria nor Credo, common Preface
N.B. More information on Ember Days can be found in Rubrical FAQs.
Matins: Invitatorium Prope est iam; Hymn Verbum supernum; Friday psalms and antiphons; no Te Deum
Lauds: Friday psalms of the 2nd scheme; antiphons are proper (they are given in the psalter: Feria VI ante Vigiliam Nativitatis Domini); Hymn En clara vox; preces are said
Hours: Friday psalms with antiphons from Lauds
Vespers: Friday psalms and antiphons; Hymn Creator alme siderum; Magnificat O Rex gentium (O Antiphons for Advent); preces are said