of Pontia." It was this younger Domitilla who was accompanied in her exile by her two Christian servants, Nereus and Achilles; whose banishment is spoken of by St. Jerome as "a life-long martyrdom,"--whose cell was afterwards visited by Sta. Paula,[221] and who, according to the Acts of SS. Nereus and Achilles, was brought back to the mainland to be burnt alive at Terracina, because she refused to sacrifice to idols. The relics of Domitilla, with those of her servants, were preserved in the catacomb under the villa which had belonged to her Christian aunt. Receiving as evidence the story of Sta. Domitilla, this catacomb must be looked upon as the oldest Christian cemetery in existence. Its galleries were widened and strengthened by John I. (523--526). A chamber near the entrance is pointed out as the burial-place of Sta. Petronilla. "The sepulchre of SS. Nereus and Achilles was in all probability in that chapel to which we descend by so magnificent a staircase, and which is illuminated by so fine a _luminare_; for that this is the central point of attraction in the cemetery is clear, both from the staircase and the luminare just mentioned, as also from the greater width of the adjacent galleries and other similar tokens." Here then St. Gregory the Great delivered his twenty-eighth homily (which Baronius erroneously supposes to have been delivered in the Church of SS. Nereo ed Achilleo, to which the bodies of the saints were not yet removed), in which he says--"These saints, before whose tomb we are assembled, despised the world and trampled it under their feet, when peace, plenty, riches, and health gave it charms." " ... There is a higher and more ancient _piano_, in which coins and medals of the first two centuries, and inscriptions of great value, have been recently discovered. Some of these inscriptions may still be seen in one of the chambers near the bottom of the staircase; they are both Latin and Greek; sometimes both languages are mixed; and in one or two instances Latin words are written in Greek characters. Many of these monuments are of the deepest importance both in an antiquarian and religious point of view; in archaeology, as showing the practice of private Christians in the first ages to make the subterranean chambers at their own expense and for their own use, _e. g._--'M. Aurelius Restutus made this subterranean for himself, and those of his family who believed in the Lord,'--where, both the triple names and the limitation introduced at the end (which shows that many of his family were still pagan), are unquestionably proofs of very high antiquity."--_Northcote's Roman Catacombs_, p. 103, &c.