Marriages, mixed, in pagan Rome, 15; Tertullian on, 15. Martial, Valerius, house of, 192. Martyrs, early, 3; their alleged stupidity, 7; stones said to be tied to the necks of, 39, 41; love-feasts celebrated near their tombs, 42; their tombs decorated with flowers, 49; their burial and tombs, 119; scene of the first martyrdoms, 127; churches connected with their houses, 158; their tombs in the Catacombs, 322; their bodies translated from suburban cemeteries to the city, 325; bas-relief representing an execution, 339 (cut). Mausolea. See _Tombs_. Mellini, Pietro and Mario, 166. Memoriæ, 42. Messalina, 277. Meta, its signification lost, 128. Meta di Borgo, 27. Michael, archangel, summits of hills consecrated to, 226; the statue on the mausoleum of Hadrian, 227, 228 (cut). Michelangelo, his first design for S. Peter's, 146. Military inscriptions from the Prætorian camp, 351. Military service of Christians under the Roman Empire, 18. Minerva in Christian art, 25; honored as a restorer of hair, 63. Monastery of S. Alessio, 235; of S. Andrew, 229, 230 (cut). Monte Mario, 165. Monte Testaccio, 181. Mosaics, in church of S. Paolo alle Tre Fontane, 25; in church of S. Andrea, 29 (cut); in church of S. Pudentiana, 113; in S. Peter's, 139. _Mundus muliebris_, 204. Museo delle Terme, 268. Museums. See _Capitoline_, _Lateran_, _Vatican_; also _dei Conservatori_, under _Palaces_. Music, religious, school of, established by Gregory, 229. Naples, church of the Olivetans, 25. Nemi, the site of a temple of Diana, 60 (cut). Neptunium. See _Temple of Neptune_, 99. Nereus and Achilleus, martyrs, 337. Nero, 127, 287; relation to Christianity, 11; deserted by the legions, 185; head of, 186 (cut); his flight and death, 187; his funeral, 189; his tomb, 189. Nerva, 177. Nicomachus Flavianus, attempt to restore paganism, 97. Oaths, 105. Obelisks, discovered in Rome, 92, 97, 172; of Rameses the Great, discovered in 1883, 95. Oils, 218. Oratories, private, of the early Christians, 109. Orientation of churches, 120, 152. Orpheus, in Christian art, 23 (cut). Ossaria, 256. Ostia, imperial palace at, 25; granary at, 47 (cut). Otho II., his tomb, 136. Pacuvius, 69. Pætus, Lucilius, tomb of, 283. Pagan rites and customs adopted by the Church, 23. Paintings, fresco in S. Clemente, translation of Cyril's remains, 32 (plate); in a patrician house in the Farnesina gardens, 263, 264 (plate), 265 (cut); in the Catacombs, discovered in 1714, 330; in the Villa Amaranthiana, 335; of the Saviour with SS. Paul and Peter in the Catacomb ad Duas Lauros, 356; of the story of Jonah and the Symbolic Supper, 356, 357 (cut); illustrations of the Gospel in the Catacombs, 358; battle between Constantine and Maxentius, _frontispiece_.