In seasons favourable to them the Oven-birds build in autumn and winter, and breed early in spring; so that their broods are out of their clay-houses by the end of October or earlier; when this happens, the Swallow that breeds in November quietly takes possession of the forsaken fortress. But accidents will happen, even to the wonderful fabric of the Oven-bird. It is sometimes destroyed and must be rebuilt; or its completion has perhaps been retarded for months by drought, or by the poor condition of the birds in severe weather; or the first brood has perhaps perished, destroyed by an opossum or other enemy. November, and even December, may thus arrive before some pairs have hatched their eggs; and it is these unfortunate late breeders that suffer from the violence of the marauding Swallows. I have often witnessed the wars of these birds with the deepest interest; and in many ovens that I have opened I have found the eggs of the Oven-birds buried under the nests of the Swallows. After the Swallows have taken up a position near the coveted oven, they occasionally fly towards and hover about it, returning again to their stand. By-and-by, instead of returning as at first, they take to alighting at the entrance of the coveted home; this is a sort of declaration of war, and marks the beginning of hostilities. The Oven-birds, full of alarm and anger, rush upon and repel them as often as they approach; they retire before this furious onset, but not discomfited, and only warbling out their gay seemingly derisive notes in answer to the outrageous indignant screams of their enemies. Soon they return; the scene is repeated; and this desultory skirmishing is often continued for many days. But at length the lawless invaders, grown bolder, and familiar with his strength and resources, will no longer fly from the master of the house; desperate struggles now frequently take place at the entrance, the birds again and again dropping to the ground clutched fiercely together, and again hurrying up only to resume the combat. Victory at last declares itself for the aggressors, and they busy themselves carrying in materials for their nest, screaming their jubilant notes all the time as if in token of triumph. The brave and industrious Oven-birds, dispossessed of their home, retire to spend their childless summer together, for the male and female never separate; and when the autumn rains have supplied them with wet clay, and the sense of defeat is worn off, they cheerfully begin their building-operations afresh.