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24 be found along: these railways, and the Sparrows naturally follow wherever food is found. To a lesser degree carriage roads have served the same purpose, the food furnished in the latter case being mainly the partially digested grain in horse droppings.

This gradual spread may take place at any season of the year, but probably is most pronounced in late summer and autumn, for reasons which will at once appear. It has been repeatedly remarked that when Sparrows are first introduced to a new region it is impossible, without actual confinement, to keep them on a farm near a town or city. They soon abandon the country for the city, and, except at harvest time, seldom return to the farm where they were introduced until the city becomes crowded. This may mean until there is no longer an ample supply of food for all the Sparrows, or, more commonly, it means until there are no longer enough convenient breeding places for all. In most cases it is the young which are thus crowded out, and consequently in midsummer and early autumn flocks of young birds may be met with far out in the country, wherever food is abundant, and when this food fails, or the ground becomes covered with snow, they retreat to the nearest towns, villages, or even farmhouses, often at considerable distances from the places where they were reared. But, in most cities, a time arrives at last when more Sparrows collect in winter than can possibly find nesting places in spring. Then, when all desirable places have been occupied, the remaining birds are forced to go to other towns or villages, or to nest in the country.

In this way the country for miles about large cities becomes fairly crowded with Sparrows, if the food conditions are favorable, and then the Sparrow shows his great power of adaptation by constructing nests for himself in trees. Twenty years ago there were few places in this country where any such Sparrow nests could be found, but to day they are common almost everywhere, and frequently they are used as places of shelter and retreat in severe winter weather, as well as for breeding places in summer. At first, evergreen trees are preferred, and a bulky nest, hardly more than a large, irregular heap of straw and rubbish, is built; but as such trees become crowded, or as the Sparrows gain skill in building, other trees are used, and often the nests are smaller and more symmetrical. The nests of native birds also are often utilized as foundations, the rightful owners being driven off first. In places where Sparrows find abundance of food and congenial surroundings, they increase to such an extent that these nests seriously disfigure the shade trees, and by their filth even injure them. Mr. Ridgway, of the Smithsonian Institution, says:

The English Sparrow has been in Wheatland, Ind., since 1877, and is now very abundant. I recently counted twenty-one of its large nests on one oak tree by the roadside, a little distance outside of the village. (Washington, D. C., February 11, 1888.)

It may seem superfluous to many readers to introduce any evidence showing that the Sparrow is not confined to cities, but so many persons