The second natural division consists of _central Italy_, which, however, has very different boundaries from those marked in our maps. The southern frontier has already been fixed by what I said before; but the northern runs along the Aesis from the borders of Marca Ancona, the ancient Picenum, across the ridge of the Apennines, so that the sources of the Tiber still belong to central Italy; it then passes along the Apennines on the frontiers of the territory of Bologna to the point where the Apennines unite with the Alps, so that even the coast of Genoa belongs to this part of Italy. This division is likewise based upon the vegetation. Its high mountainous parts have of course a lower temperature than the valleys, though they are by no means thoroughly different; they belong as parts to the whole, as every whole consists of several and diverse parts. Their character, on the other hand, is quite different from that of the opposite heights, which, under the same degree of latitude, descend into Lombardy. This division, then, with the exception of its highest mountain regions, is the country of the olive-tree, whence the excellent olive plantations in the territories of Lucca and Genoa, and also in Marca Ancona. In the south-western parts of Italy, as, for example, at Naples, the olives are not of equal value, though they are still excellent. The race of men in central Italy has less of the southern character; they still share with the southern people the development of the muscular fibres, though they have it in a less degree; but their features are less harsh, the forms being more round and fleshy; yet these features differ according to the different districts and races.