inhabitants regularly take the eggs, only allowing them to begin to brood eight or ten days before Midsummer. Should a man approach their nests, both male and female endeavour to defend it, and raise a terrible outcry. The young are clothed in down, of a greyish black above and white on the under surface; they soon run about, and for some days are assiduously fed with small fishes, which are brought to them by both parents. * * * * * The RIVER TERNS (_Sterna_) are distinguished from the preceding birds by their somewhat arched, moderately short beak, small short-toed feet, and deeply-forked tail; and by their frequent occurrence at the mouths or along the banks of rivers, or of inland streams or lakes. In size they are considerably smaller than the Caspian Terns, and their flight is much more graceful and Swallow-like, always exciting the admiration of the beholder. THE COMMON TERN. The COMMON TERN (_Sterna hirundo_, Coloured Plate XXXVIII.), when in its adult plumage, closely resembles the Caspian Sea Swallow, but may be recognised by its inferior size, the grey colour of the under parts of the body, and by its red feet. In young birds the plumage of the back, like that of the preceding species, is transversely spotted with brown, but the feet are of a yellowish shade. The length of this species is from sixteen to seventeen inches; of these six and a half belong to the tail, the fork being four inches deep; the span of the wings is twenty-three inches. It is at present uncertain whether all River Terns are to be regarded as belonging to this species or not. Should they be found to do so, their habitat must extend throughout the whole north temperate zone, seeing that they are pretty equally distributed in the eastern and western hemispheres. They are met with more frequently than other Terns in the vicinity of rivers and lakes of fresh water. As these birds make regular migrations, they are only seen at their breeding-places in the summer, appearing during the last days of April or the beginning of May, and in July or August preparing for their departure. They spend the winter in the south of Europe, or in the north of Africa, where at that season they are very common. When on their journeyings they fly leisurely, and at a considerable elevation, from one sheet of water to another, generally following the course of streams and rivers, to which, if pressed by hunger, they repair, in order to obtain food and rest. Arrived at their destination, they settle themselves either in the vicinity of the sea, or near fresh water, without seeming to have any decided preference for either.