One might assume that Introits belong to the least variable elements of the Latin liturgical repertory. This is indeed so, in so far as the Temporal and the ancient layers of the Sanctoral are concerned. Even in these parts, however, remarkable differences appear on vacant and supplementary Sundays, in the context of vigils and octaves, and due to the interference of thematically related items. Yet a comprehensive survey reveals far more peculiarities, both ancient and modern. The composition of votive Masses diverges quite often. Some sources contain archaic introits for saints that fell into disuse in other places or were only locally transmitted. Others adopt the pieces of other genres, antiphons or processional chants as Introits, mostly a late but surprisingly widespread phenomenon. It seems that already in the last centuries of the Middle Ages there emerges the category of merely textual propers: items that have never been sung or furnished with any melody as they were exclusively used within votive low Masses. Plenty of them appears in early modern Missals but the discovery of their medieval forerunners is a relative novelty.
In the last few weeks, we checked and standardized every Introit that had been uploaded to Usuarium before. All the records are attached now to a standard incipit and an identification number in parentheses, derived from the Cantus Index. The standard items can be consulted in the synopsis according to their assignment to days and topics and searched for in the Research/Conspectus menu. Several divergent assignments and 83 Introits beyond the scope of the Cantus Index have been identified.
As it is well known, the choice of verses can also vary and, at some points, this is an integral feature of a particular Use's identity. Therefore, Introit verses have been standardized along with their antiphons and listed accordingly. We continue the work with the graduals and the next genres of the chanted propers.