Founded by Pius IX., and composed of Christian antiquities. There are many bas-reliefs, fragments, inscriptions, mosaics, &c., worthy of admiration. The CORRIDOR, _upstairs_, is decorated with Christian inscriptions from the Catacombs. The oldest is A.D. 238. They relate to persons, dogmas, rites, and ranks of the clergy of the early Christians. From the end of the corridor on the left two rooms open out, ornamented with copies of frescoes found in the Catacombs. _Sometimes the entrance is made from the court through the_ LONG HALL.--Sitting statue of S. Hippolitus, found near S. Lorenzo fuori le mura. On the chair is the Paschal Calendar in Greek, composed A.D. 223, and a list of Hippolitus's writings. LANDING OF THE STAIRS.--Bas-relief of Elijah ascending to heaven. This hall is decorated with a number of sarcophagi of the early Christians, found in the early churches and catacombs. They are placed so as to illustrate how the tombs were situated in the vestibules of the catacombs. _From the Loggia upstairs we enter the_ PICTURE GALLERY. FIRST ROOM, or Mosaic Hall.--This beautiful mosaic was found in the Baths of Caracalla, and represents full length figures and busts of boxers, each occupying a separate panel, some having the names upon them. The walls are decorated with scenes from the life of Constantine the Great. SECOND ROOM.--Early medieval frescoes from old churches. Frescoes cut from the walls of the Church of S. Agnese fuori le mura. Paintings of prophets and birds, from the crypt of the Church of S. Nicolò in Carcere. THIRD ROOM.--_We commence with the left-hand wall immediately on entering the different rooms._ Crowning the Madonna, by Lippi; S. Thomas receiving the Belt from the Virgin, by Benezoto Gozzoli; Scenes from Life of the Virgin, by the same; S. Antonio, by Antonio di Murano; Madonna, by Carlo Crivelli, 1482; Virgin and four Saints, by Bartolo di Murano, 1481; Assumption, SS. Lawrence and Benedict, Catherine and Gertrude--all three by Cola di Amatrice, 1515; S. Jerome, by Santis, _in tempera_; mosaic flooring from the Palazzo Sorra on the Via Nazionale. FOURTH ROOM.--Holy Family, by Andrea del Sarto; Annunciation, by Francia; Virgin and Saints in fresco, by Botticelli; Crucifixion, a fresco; Baptism of Christ, by Cæsar da Sesto; a panel, by Perugino; copy of the Transfiguration; copy of Giulio Romano's Coronation; Deposition, by Luca Signorelli; S. Stephen, a sketch, by Giulio Romano. _From here we enter into two off-rooms containing_ statues, busts, and reliefs, representing North American Indian life, by Pettrich. FIFTH ROOM.--Madonna of the Belt, by Spagna; the Virgin with S. John and S. Jerome, by Marko Palmezzano, 1500; three tapestries; S. Peter, by Fra Bartolomeo; Sixtus V., by Domenichino; S. Paul, by Bartolomeo; Madonna and Saints, by Palmezzano; Sixtus V. as Cardinal Peretti, by Sassoferrato; mythological subject, by Paul Veronese; a Pagan Sacrifice, by Caravaggio.