NEMORENSIS LACUS (mod. Nerni)  , a

lake in the Alban Hills, in an extinct subsidiary crater in the outer ring of the ancient Alban crater, E. of the Lake of Albano . It is about AM. m. in diameter and some s so ft. deep; the precipitous slopes of its basin are over 300 ft. high, and on the side towards the modern village a good deal more, and are mainly cultivated . It is now remarkable for its picturesque beauty . In ancient times it was included in the territory of Aricia_ and bore the name " Mirror of Diana." The worship of Diana here was a very ancient one, and, as among the Scythians, was originally, so it was said, celebrated with human sacrifices; even in imperial times the priest of Diana was a man of low condition, a gladiator or a fugitive slave, who won his position by slaying his predecessor in fight, having first plucked a mistletoe bough from the sacred grove, and who, notwithstanding, bore the title of rex (king) . It is curious that in none of the inscriptions that have been found is the priest of Diana mentioned; and it has indeed been believed by Morpurgo and Frazer that the rex was not the priest of Diana at all, but, according to the former, the priest of Virbius, or, according to the latter, the incarnation of the spirit of the forest . The temple itself was one of the most splendid in Latium; Octavian borrowed money from it in 31 B.C., and it is frequently mentioned by ancient writers . Its remains are situated a little above the level of the lake, and to the N.E. of it . They consist of a large platform, the back of which is formed by a wall of concrete faced with opus reticulatum, with niches, resting against the cliffs which form the sides of the crater . Excavations in the 17th and the last quarter of the 19th centuries (now covered in again), and also in 1905, led to the discovery of the temple itself, a rectangular edifice, 98 by 52 ft., and of various inscriptions, a rich frieze in gilt bronze, many statuettes (ex-votos) from the favissae of the temple in terra-cotta and bronze, a large number of coins, &c . None of the objects seem to go back beyond the 4th century B.C . A road descended to it from the Via Appia from the S.W., passing through the modern village of Genzano . The lake is drained by a tunnel of about 2 M. long of Roman date .

On the W. side of the lake remains of two

ships (really floating palaces moored to the shore) have been found, one belonging to the time of Caligula (as is indicated by an inscription on a lead pipe), and measuring 210 ft. long by 66 wide, the other even larger, 233 by 8o ft . The first was decorated with marbles and mosaics, and with some very fine bronze beamheads, with heads of wolves and lions having rings for hawsers in their mouths (and one of a Medusa), now in the Museo delle Terme at Rome, with remains of the woodwork, &c., &c . Various attempts have been made to raise the first ship, from the middle of the 15th century onwards, by which much harm has been done . The neighbourhood of the lake was naturally in favour with the Romans as a residence . Caesar had a villa constructed there, but destroyed again almost at once, because it did not satisfy him . See F . Barnabei, Notizie degli scavi (1895), 361, 46r; (1896), 188 ; V . Malfatti, Notizie degli scavi (1895), 471; (1896), 393; Rivista marittima (1896), 379; (1897), 293; J . G . Frazer, The Golaen Bough (London, 1900) ; L . Morpurgo in Monumenti dei Lincei, xiii . (1903), 297 sqq .

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