TRATTO (Tractus). — This is Gradual (v.) and takes the place of the Alleluia during the penitential seasons from Septuagesima to Easter, at Masses for the dead, and on certain other days (vigils, etc.). It consists of two, three, four, or even more verses, which in Christian antiquity were sung by a single cantor, and later by two at the ambo, consecutively (tractim), that is, without antiphonal or responsorial interruptions by the choir.
At first the t. followed the second scriptural reading that preceded the Gospel, while the Gradual followed the first; but when the first or second reading was suppressed, the t. came to be joined immediately to the Gradual. After the singing of the Alleluia was introduced (Gregorio M.) and extended to all the feasts and Sundays of the year, the t. remained for the Sundays of the penitential seasons, during which the Alleluia is omitted; the t. « Domine non secundum » of the Mondays, Wednesdays, and Fridays of Lent is a Gallican importation of the 8th century, originating in the liturgy for penitents (Jungmann), because ferial days with a single prophetic reading ordinarily had only one chant, namely, the Gradual. The melodies of the t. are regarded by Wagner as « most ancient and venerable monuments of Latin ecclesiastical chant ».
Wagner explains the Latin term tractus as the equivalent of the Greek εἰριός = hirmor, that is, of a typical melody for intoning the various parts of a hymn; the t. would be nothing other than the primitive Gradual, namely, a responsorial psalm dating from the 4th or 5th century, in which the responsory was omitted before the abbreviation of the texts for the enrichment of the melodies. Therefore the t. should not be regarded as a chant of mourning or penance; but since the season of Lent has preserved the ancient elements of the liturgy, it has also preserved the ancient Gradual, called t., with its most ancient melodies.