The hypothesis that our now _numerous_ sparrows, being descended from a _few_ European birds, and that, probably, continual and close reproduction among individuals of the same stock, as in the case of our original _few_ sparrows, has encouraged weakness in the race, can hardly serve as an explanation of this phenomenon, because the sparrow is so prolific that, after a few years, so many families had been formed that the relation between them became very distant. The reason for the greater proportion of albinism found in the young is obvious; the young sparrows affected with albinism, lacking usually the physical strength to battle their way in life, meet death prematurely, and thus a very small proportion of the number is permitted to reach maturity, while those that do owe it to some favoring circumstance. Many are picked up and cared for by the public; and among those to whom these sparrows generally owe such prolongation of life are the policemen in our public parks, who often bring these little waifs to their homes, keeping some, and sending others out into the world, after caring for them until they have acquired the sufficient strength. However, almost all of these albino-sparrows are picked up by the cat, and immediately disposed of to the feline's physical benefit. They form such a prominent diet among the cats near Washington Park, where I live, that, upon the removal of some of our neighbors to the upper part of the city, it was noticed that their cat became dissatisfied and lean, as sparrow-meat is not to be found so extensively there, but it finally became resigned, finding it possible to procure about three sparrows daily. And here attention should be called to the method employed by our cats to catch not only the weak, but fine, healthy sparrows as well; it ought perhaps to be looked upon as a mark of intellectual improvement, for originally their attempts consisted chiefly in a very unsuccessful giving chase to the flying bird, whereas the cats of to-day are skilled in a hundred adroit devices. It has often been a source of enjoyment to watch their well-laid schemes and delicate maneuverings. What wonder then, with such dainty fare at his disposal, that the cat is often found to have become indifferent to rats, and even to mice? There are several notable changes, no more desirable than the foregoing, which have been caused by the introduction of the house-sparrow. The only positive benefit which occurs to me is that the measuring worm, which formerly infested all our vegetation, is now very nearly extinct through the instrumentality of the sparrows. A pair of these, during the breeding-season, destroys four thousand larvae weekly. In some places, complaints are made that their untidy nests mar the appearance of trees and walls.