Frontinus tells us that the aqueduct of Nero terminated at the temple of Claudius, which was in the centre of the Claudium; this was in fact the sacred enclosure round his temple. A fragment of the Marble Plan of Rome also confirms this, but it is equally clear that soon after the time of Claudius and Nero the water was carried on in three branches, one to the Aventine, another to the Palatine, and the third to the Colosseum, as has been before stated, and there are remains of the arcades of each in all three directions. The _specus_ found in April, 1876, under the garden of the Marchese Rappini, must have come from the reservoir mis-called the _vivarium_, but it had been long out of use. Many other remains of the aqueducts within the walls of Rome have been found during the great excavations of 1874-1876, in different parts of the city. Some of these have been already mentioned. Dr. Fabio Gori has sent me an important notice of some excavations recently made between Subiaco and Vico Varo, which throw new light on the line of the _specus_, or channels of the aqueducts, in several places. On p. 13, note h, it is stated that “the Anio Vetus has its source in the district called _La Connotta_, and passes under the hill of Marano;” but it now appears that the aqueduct in La Connotta belongs to the Anio Novus, because they have discovered at the sources of the Aqua Marcia another aqueduct on a lower level, which must be the Anio Vetus. This is on the opposite side of the river Anio, and passed over the river on the bridge at Vico Varo, of which the great stone piers remain in the bed of the river. He could not find the sources of the Anio Vetus at the fortieth mile, near the bridge of Agosta (twenty miles above Tivoli), because the torrents, in time of flood, have brought down such a quantity of stone in the bed of the river Anio, and the valley through which it flows, that the level of the ground, and of the bottom of the river in this part, is now nearly twenty feet higher than it was when that aqueduct was made. At p. 60, it is said that Dr. Gori had found the _Piscina Limaria_ of the Anio Novus, made by Claudius, “at the _Prata della Cartiera_ of Subiaco;” that was written when they had found a large aqueduct by the side of the _Emissarium Barberini_; but the recent excavations have shewn that the water for that aqueduct came from the third loch, near the bridge of S. Mauro, where the opening at the entrance to the _specus_ was found, covered with an iron grating. From this it was inferred that there was a special aqueduct with a private _specus_ to supply the baths and thermæ of the _Villa Neronis Sublacensis_. A quantity of marble of very rare kinds, from this villa, on the margin of the river, has been found, and in the bed of the river the foot of a colossal bronze statue.