that he has usually found the egg of the Cuckoo in the nests of the following species :—Common, Reed, and Yellow Buntings, Robin, Flycatcher, Greenfinch, Chaftinch, Linnet, Hedge-Accentor, Pied and Yellow Wagtails, and Tree- and Meadow-Pipits, occasionally in those of the Skylark, Chiff-Chaff, and Willow-Wren ; in One instance in that of a Blackbird, in another in that of the Red-backed Shrike, and thrice in those of the Dartford Warbler. Dr. Baldamus, in ‘ Naumannia,’ 1853, p- 307, has some most interesting remarks on the fact, as he con- siders it, that the egg of the Cuckoo is always found to present a very recognizable resemblance to the normal appearance of the egg of the species in whose nest it is deposited. In ‘ Naumannia,’ 1854, p. 415, he gives a list of references to a plate in which are figured sixteen Cuckoo’s eges, selected to show that this is the case. The similarity in many instances is very obvious, and the subject of the article, which does not seem to be generally known to British ornithologists, deservedly merits further attention. If the Doctor’s assertion be true, it adds still more to the wonderfully mysterious economy of this bird. Mr. Alfred Newton informs me that he has more than once found two Cuckoo’s eggs deposited in the same nest. He also tells me that it not unfrequently lays its eggs in the nest of the Brambling in Northern Lapland. ' Although so much has been written on the means by which the egg is deposited in the nest, yet nothing quite positive has been ascertained ; but a considerable amount of certainty has been the result of repeated watchings. The generally received opinion is, that the Cuckoo drops her egg on the bare ground, carries it in her mandibles, and places it in the foster-nest ; indeed there are such nests, as those of the Wren and the Robin, which, when built in the hole of a wall, will admit of no other means of deposit ; certain it is that the eggs of the little green Chalcites of Australia cannot have been placed in the domed nests of the Malui in any other way. When the Cuckoo takes up its station near a garden, it hunts, in the early morning, the ivy-clad wall for the nest of the Wagtail as closely as a schoolboy, next the espalier-apples trained beside the walk, the flower-covered trellis over the door of the mansion, the Wistaria upon the railing of the steps, or wherever it is likely the bird may have fixed upon for a breeding-place ; at other times it watches the Wagtail flying from the boat-house, on the rafters of which, or among the thatch, it may have placed its nest. It will resort to the more exposed nest of the Flycatcher, often in close proximity to the house; or the actions of the Robin or the Wren may attract its attention to the hidden nest on the bank-side. These depositories once discovered, the egg is inserted at the proper moment for the development and well-being of the future nestling. The following notes on the nidification of the Cuckoo were the result of some observations made by myself in the garden of Mr. De Vitre’, at Formosa, near Maidenhead, in Berkshire, in May and June 1860. A pair of Wagtails had built a nest on a beam of the boat-house, two yards distant from the edge of the roof, and, when first noticed, were in a state of great excitement from the presence of a Cuckoo. The latter succeeded in depositing an egg, which, with those of the Wagtails, was taken on the 21st of May. In the beginning of June, Briggs (the gardener) and myself observed another Cuckoo hunting the espalier apple-trees in the inner garden; among which we afterwards found a Wagtail’s nest with five eges— four belonging to the little architect, and one to the parasite ; when first seen, the latter was on the outside of the others. On the 18th all the eggs were hatched, nearly simultaneously ; and the young Cuckoo and the young Wagtails continued to occupy the nest in company until the third day, when, at five o’clock in the morning, the latter were found dead on the border beneath the tree: the parasite had now the nest all to itself, and, when I examined it on the 22nd, was still callow, helpless, and blind. On the evening of the 6th of July, the young Cuckoo was just able to hop out of its nest, and could even manage to fly a short distance. Its weight at this time was exactly three ounces. The eggs of the Cuckoo simulate so closely, both in size and colouring, those of most of the birds to whose care they are confided, that to many persons they would be undistinguishable. How singular it is that the eggs of so large a bird should be so small! Here again is mystery, fraught with thought and interesting speculation for the theorist. The development of the chicks in the egg of the parasite and in those of the fosterparent, whatever it may be, goes on simultaneously, and all are hatched as near the same time as possible, that is, in about twelve or fourteen days. For the first two or three days the callow, blind, and helpless young can scarcely be distinguished one from the other ; by the end of that time the parasite is generally left sole tenant of the nest, and if search be made for its late companions, they will be found dead on the ground. As to how they are ejected there is much diversity of opinion: the general belief is that they are shouldered out by the parasite ; but from this I entirely dissent, for the simple reason that, judging from my own observation, I do not believe that at the end of the third day the parasite has the physical power requisite to eject the rightful possessors from a deep cup-shaped or a domed nest. By whom then is this unseemly cruelty performed ? Is it by the old Cuckoo, which is constantly seen in the neighbourhood of the nest, or by the fosterparents ? May we not more readily imagine that it has been done by the latter, who, having bestowed all their attention on the parasite, thus cause the death of their own young, which are then cleared out of the nest in the same way as broken eggshells, feces, and other extraneous matters ? their joy by of delight. and there syllables ¢/ As some and whithe their winte to and fro Cuckoo sy is alike vis dant in ev at the oy whose fau but not ye as well as coloured ¢ trees, the ordinary 8 A youn Very stro1 protruded Precisely immediate the bird and cater not this I delicate e birds at a attended Period of against, th