Rogation Days, in the calendar of the Western Church, four days traditionally set apart for solemn processions to invoke God's mercy. They are Apr. 25, the Major Rogation, coinciding with St. Mark's Day; and the three days preceding Ascension Day, the Minor Rogations. The processions are Christian adaptations of Roman pagan ones; in rural districts they are regarded as blessing the fields. The prayers include the Litany of the Saints (see litany). Such liturgical usages are no longer prescribed in the universal Roman Catholic liturgical calendar; observance is left to the discretion of the national councils of bishops.