S. Valentinus is the last of our long catalogue of subterranean cemeteries. Little is known of the confessor and martyr after whom this Catacomb is named. His “Acts,” as we possess them, were only compiled in the sixth century. Valentinus suffered martyrdom _circa_ A.D. 268-70. (Claudius Gothicus was then Emperor.) He is stated to have been a Christian priest and physician. The martyr’s body was recovered by Sabinilla, a Christian lady, and was buried near the place where he suffered. The desire to be buried near S. Valentinus led to further excavations, but the tufa in this place was too hard and did not lend itself to the formation of galleries. Corridors were excavated above the tomb of the martyr; little, however, of interest has been found as yet. A third gallery was also constructed. It was the second gallery above the grave of the martyr which became the public cemetery, but it has been only very partially examined; much is still blocked up. Some time after the Peace of the Church, under Pope Julius, A.D. 337-52, a basilica named after S. Valentinus was built a little to the right of the martyr’s crypt. This church was restored, probably rebuilt, by Pope Honorius I, A.D. 625-38. The ruins of this Church of S. Valentinus have been recently brought to light. The Itineraries speak of the body of S. Valentinus as in the restored basilica. These sacred remains were, as in other cases, no doubt translated from their original resting-place into the church above. The bodies of other martyrs who probably suffered in the Diocletian persecution are alluded to in the Pilgrim Guides. In the ruins of the basilica a chapel was identified by an inscription as having been dedicated to certain of the local martyrs, and with these nameless saints S. Zeno is mentioned by name. S. Zeno was evidently once highly venerated. His presence here is accounted for by a notice in one of the Itineraries, which styles him “frater Valentini,”--possibly only signifying “frater in Passione.” S. Zeno was buried in the well-known Cemetery of Prætextatus on the Appian Way. He is perhaps best known now from the famous Chapel of S. Zeno in the Church of S. Prassedis, the work of Pope Paschal I--usually called the “Orto del Paradiso.” A mosaic in that beautiful chapel pictures the two martyrs S. Valentinus and S. Zeno together. APPENDICES APPENDIX I.--ON S. PETRONILLA