Sunday within the Octave of the Assumption, the XIV Sunday after Pentecost and the 3rd Sunday of August, semi-double rite.
The texts are of the Sunday but all hymns of Iambic metre are sung to the BVM tone due to the Octave. At Lauds a commemoration of St. Hyacinth, the Octave of the Assumption and the Octave Day of St. Lawrence.
Ordinarily on Sundays within Octaves only the Octave is commemorated and there are no 'prayers for the season' as there would normally be on a Sunday. However, all occurring feasts are commemorated. In Mass the Gloria, the same commemorations as at Lauds, Creed, Preface of the Trinity.
Prior to the 1911-13 reform today was kept as the feast of St. Joachim, Father of the BVM. Provision was made by that reform for one Solemn Votive Mass of St. Joachim to be sung today with a commemoration of the Sunday and last Gospel of the Sunday, celebrated in white vestments.
At Vespers a commemoration of the Octave is made, St. Hyacinth and St. Agapitus.