As it coincided with her "octave-day" a legend grew, saying that she appeared on this day to her parents praying at her tomb, surrounded by a "bevy of virgins" (Introit), resplendent with light. "On her right hand was a lamb whiter than snow: it was Christ consecrating His union with His spouse."
Vultum tuum deprecabuntur omnes divites plebis: adducentur regi virgines post eam: proximae ejus adducentur tibi in laetitia et exsultatione. * Eructavit cor meum verbum bonum: dico ego opera mea regi.
All the rich among the people shall entreat thy countenance: after her shall virgins be brought to the King: her neighbours shall be brought to thee in gladness and rejoicing. * My heart hath spoken a good word: I speak my works to the King.
(Psalm 44:13-16,2 from the Introit of Mass)Deus, qui nos ánnua beátae Agnetis Vírginis et Martyris tuae sollemnitáte laetíficas: da, quaesumus; ut, quam venerámur officio, étiam piae conversatiónis sequámur exémplo.
O God, who each year dost gladden us by the feast of blessed Agnes, Thy virgin and martyr, grant, we beseech Thee, that while venerating her memory, we may ever strive to model our lives after her holy example.
Stans a dextris ejus Agnus nive candidior, Christus sibi sponsam et Martyrem consecravit.
Christ stood at hand, even he that is as a Lamb whiter than snow, and consecrated her to himself, to be his bride and Martyr.
(Commemoration from Vespers)
From the Catholic Encyclopaedia: http://www.newadvent.org/cathen/01214a.htm