They may be enumerated, proceeding from Rimini southwards: (1) the Foglia; (2) the Metauro, of historical celebrity, and affording access to one of the most frequented passes of the Apennines; (3) the Esino; (4) the Potenza; (5) the Chienti; (6) the Aso; (7) the Tronto; (8) the Vomano; (9) the Aterno; (10) the Sangro; (11) the Trigno, which forms the boundary of the southernmost province of the Abruzzi, and may therefore be taken as the limit of Central Italy.
In all the upland valleys of the Abruzzi snow begins to fall early in November, and heavy storms occur often as late as May; whole communities are shut out for months from any intercourse with their neighbours, and some villages are so long buried in snow that regular passages are made between the different houses for the sake of communication among the inhabitants.
Birth and marriage rates vary considerably, being highest in the centre and south (Umbnia, the Marches, Apulia, Abruzzi and Molise, and Calabria) and lowest in the north (Piedmont, Liguria and Venetia), and in Sardinia.
The death-rate is highest in Apulia, in the Abruzzi and Molise, and in Sardinia, and lowest in the north, especially in Venetia and Piedmont.
Silkworm-rearinr establishments of importance now exist in the Marches, Umbria, in the Abruzzi, Tuscany, Piedmont and Venetia.