A variety of forms occur in these openings of the cathedral of Como, like so many experiments in fanciful composition without any basis of reason. The window, for instance, of the bay adjoining that here represented, seems to show that the designer felt dissatisfied with the small pilaster set upon the larger one, and accordingly omitted it, a moulding on the edge of the spandrel, profiled like the lower member of the crowning entablature, taking its place. But again, as if he now felt that the entablature required a more architectural support, he has in another window reproduced the small pilaster, but instead of a large single one below he has employed two narrow ones, thus giving separate support to the arch and the entablature. The doorway on the north side of the nave presents a further modification of the scheme. Here the jambs and the arch are splayed as before, and a tall column of the ornamental tapering form, already noticed in the windows of the Certosa of Pavia and in the chapel of St. Peter Martyr, is set on either side of the composition. This portal, like the one on the south side, has two entablatures with an arch between, and these columns reach to the upper entablature of which they carry ressauts. No great pediment crowns this doorway, but a tall niche, framed in with an order of diminutive pilasters and surmounted with a small pediment, rises over the centre of the upper entablature. This niche shelters a statue of the Virgin, and is flanked by a statue on either side. Many variants of this ornamental scheme for door and window occur in Lombardy and Venice, and it was reproduced in many other parts of Italy, occurring, as we have seen, even in Rome as in the palace of the Cancelleria and the Palazzo Torlonia. In the fifteenth century, as in the Middle Ages, the architecture of each principal locality developed peculiarities of style in accordance with its peculiar tastes and conditions. Thus the Renaissance design of Venice has a general character of its own, though it drew some of its materials from Florentine and Lombard sources. Michelozzi had followed the exiled Cosimo de’ Medici to Venice, and Vasari tells us[108] that he made there many drawings and models for private dwellings and public buildings. On the other hand a family of architects and sculptors from Lombardy, known as the Lombardi (Pietro Lombardo and two sons, Santo and Tullio), had come to Venice in the fifteenth century and introduced features from the Lombard Renaissance.