Surely our cow-bird has missed this secret haunt on her rounds. Be not deceived! Within a half-hour after this egg was laid the sparrow and its mate, returning from a brief absence to view their prize, discover two eggs where they had been responsible for but one. The prowling foe had already discovered their secret; for she, too, is "an attendant on the spring," and had been simply biding her time. The parent birds once out of sight, she had stolen slyly upon the nest, and after a very brief interval as slyly retreated, leaving her questionable compliments, presumably with a self-satisfied chuckle. The intruded egg is so like its fellow as to be hardly distinguishable except in its slightly larger size. It is doubtful whether the sparrow, in particular, owing to this similarity, ever realizes the deception. Indeed, the event is possibly considered a cause for self-congratulation rather than otherwise--at least, until her eyes are opened by the fateful _denouement_ of a few weeks later. And thus the American cow-bird outcuckoos the cuckoo as an "attendant on the spring," taking her pick among the nurseries of featherdom, now victimizing the oriole by a brief sojourn in the swinging hammock in the elm, here stopping a moment to leave her charge to the care of an indigo-bird, to-morrow creeping through the grass to the secreted nest of the Maryland yellow-throat, or Wilson's thrush, or chewink. And, unaccountable as it would appear, here we find the same deadly token safely lodged in the dainty cobweb nest of the vireo, a fragile pendent fabric hung in the fork of a slender branch which in itself would barely appear sufficiently strong to sustain the weight of a cow-bird without emptying the nest. Indeed, the presence of this intruded egg, like that of the European cuckoo in similar fragile nests, has given rise to the popular belief that the bird must resort to exceptional means in these instances. Sir William Jardine, for instance, in an editorial foot-note in one of Gilbert White's pages, remarks: "It is a curious fact, and one, I believe, not hitherto noticed by naturalists, that the cuckoo deposits its egg in the nests of the titlark, robin, and wagtail by means of its foot. If the bird sat on the nest while the egg was laid, the weight of its body would crush the nest and cause it to be forsaken, and thus one of the ends of Providence would be defeated. I have found the eggs of the cuckoo in the nest of a white-throat, built in so small a hole in a garden wall that it was absolutely impossible for the cuckoo to have got into it." In the absence of substantiation, this, at best, presumptive evidence is discounted by the well-attested fact that the cuckoo has frequently been shot in the act of carrying a cuckoo's egg in its mouth, and there is on record an authentic account of a cuckoo which was observed through a telescope to lay her egg on a bank, and then take it in her _bill_ and deposit it in the nest of a wagtail.