A still more important want of classical ages was that of the whole tribe of Agrumi, as the Italians call them—the orange, lemon, citron, and so forth. “Italy was not then,” says our Professor, “the land Wo die Citronen blühn, Im dunkeln Laub die gold-orangen glühn;” and was consequently without one of the favourite features with which æsthetic Northerns adorn their notions of Italy. They are of course absent from the frescoes. They were known to Pliny as foreign plants only. The “Median Apple” (citron) was cultivated in Italy no earlier than the third century after Christ; lemons came from the Saracens; oranges, last of all, were brought by the Portuguese from the East. The white, or silk-worm mulberry, now the commonest of all trees in the richer parts of Italy, was also unknown to the Pompeians. Its cultivation on the peninsula began, according to Schouw, in the sixth century. Silken fabrics were scarce and expensive, and imported by the Romans from the East. Voltaire somewhere makes the great superiority of a _femme de chambre_ of Madame de Pompadour over the Empress Livia consist in the unlimited enjoyment of silk stockings. It may, however, be questioned whether the Empress would have appreciated such a luxury, or whether, as the audacious French traveller, Monsieur Nodier, asserted respecting the Glasgow ladies not many years ago, she would not have got rid of such incumbrances whenever free from the restraints of company. The picturesque Carouba tree (_Ceratonia siliqua_), which now forms groves along many parts of the Italian coast, is also probably of modern introduction. We may add another more important plant which the Professor has omitted—the chestnut. Not, of course, that this magnificent native of Thessaly was unknown to Roman antiquity. It was, on the contrary, extensively cultivated in ancient Italy for its fruit. Naples was particularly famous for the excellence of its chestnuts— “Quas docta Neapolis creavit, Lento castaneas vapore tostas”— such as Martial appetisingly describes, and such as that _flâneur_ of a poet had doubtless often purchased, scalding hot, from the tripod of some hag-granddaughter of Canidia or Sagana, in the alleys of the learned city. But it was probably as yet a fruit-tree only. Introduced but two centuries before Christ,[6] it had not had time to form forests; to become, as it now is, the characteristic tree of the lower Apennines, supplanting its ancient but thriftless relative the beech, and driving the latter back to the narrow domain which it still occupies on the top of Monte Sant’ Angelo. The gnarled and twisted chestnut trunks, with their pointed foliage, under which Salvator Rosa studied his art when sojourning among the brigands at the back of Amalfi, have no counterpart in the drawings of Pompeii any more than in the poetry of Virgil.