The Alpine valleys are the most unhealthy spots of Northern Italy, for they are deprived of sunlight. Goître and idiotcy are frequent there, and in the valley of Aosta nearly all the women are afflicted with the former, owing, perhaps, to the water which flows over magnesian rocks. The inhabitants of districts traversed by numerous canals suffer from diseases traceable to miasmal effluvia. The food of the peasantry is not sufficiently nourishing or varied to counteract these deleterious influences, and many die of _pellagre_, an incurable skin disease, only known in countries where the flour of maize, in the diluted form of _polenta_, constitutes the principal article of food. In the province of Cremona one in every twenty-four inhabitants is afflicted with this malady. The sanitary condition of the people is even worse in the rice-fields of Milan and the Polesina. The women there frequently stand for hours in tepid putrefying water, and are obliged from time to time to pick off the leeches which creep up their legs.[69] But in spite of maladies, misery, and famines, always following in the train of the inundations, the fertile plain of the Po is one of the most densely peopled portions of Europe. Every plot of ground there has been utilised. The forests, very much reduced in size, harbour no game, except, perhaps, on the Alpine slopes, and even small birds are rare. Not only snipes, quails, and thrushes are shot or trapped, but also nightingales and swallows. Tschudi estimates the number of singing birds annually killed on the shores of the Lago Maggiore at 60,000; and at Bergamo, Verona, Chiavenna, and Brescia they are slain by millions, the nets being spread in the hedges of every hill. * * * * * The population of the valley of the Po is composed of the most diverse elements. Amongst its ancestors were Ligurians, probably the kinsmen of our Basks; Etruscans, famous for their works of irrigation; Gallic tribes, whose peculiar intonation is still traceable in the rural Latin spoken in Northern Italy; and Celtic Ombrians, the most remote of all, and looked upon by historians as the aboriginal inhabitants of the country. The German invasions during the first centuries of our era have left a {216} permanent mark upon the population of Northern Italy. The many tall men met with in the valley of the Po are proofs of this Transalpine influence. The Goths and Vandals, Herulians and Longobards, or Lombards, soon became merged in the Latinised masses, but their position as conquerors and feudal lords gave them an influence which their mere numbers would not have insured them. The ancient history of Lombardy is a continual struggle between the towns and these feudal lords, and as soon as the latter had been defeated—that is to say, about the beginning of the tenth century—German was superseded everywhere by Italian. [Illustration: Fig. 70.—THE GERMAN COMMUNES OF NORTHERN ITALY. Scale 1 : 650,000.]