It is remarkably gregarious, young and old congregating together, wary and watchful always, and never allowing a close approach on the land. So densely do the birds pack, that a disturbed flock taking wing looks as though the very surface of the mud or sea were rising in one solid, inseparable mass. The principal food of this Goose consists of grass, wrack, and laver. On certain mud-banks these plants grow very thickly, and to these the Brents resort as soon as the tide recedes sufficiently for them to reach and to tear up their favourite food. In studied order the birds advance, feeding as they come, sentinels remaining on the look-out in turn, until all are satisfied, or the incoming tide covers their food-plants. Then back, in a solid mass, they go towards the open sea, or to some low bank, there to rest and preen their plumage, and to wait until another tide has ebbed, and left exposed their pastures. This bird, for the most part, is a day feeder; but during moonlight nights it will visit the exposed banks, doubtless the tide having considerable influence on its habits in this respect. The flight of this Goose, if rather laboured, is powerful and well-sustained; and during its progression the birds often form into Vs or Ws, or some other lineal pattern. The note of the Brent Goose is a loud, oft-repeated, and variously-modulated _hank_ or _honk_, uttered, not only when the bird is on the ground, but during flight. But very little is known of the nidification of the Brent Goose. It breeds in the highest Arctic latitudes, selecting, if possible, an island near the coast, making a rude nest in some hollow in the ground, of dry grass, stalks of plants, and moss, and warmly lined with down. The four or five eggs are creamy-white in colour. The gander keeps watch and ward near the nest, whilst the goose incubates the eggs. By the end of July most of the Brent Geese begin to moult, and during some part of the time they are quite incapable of flight. At this critical period they keep closely to the sea. Mr. Trevor-Battye, in his interesting book, _Icebound on Kolguev_, gives a graphic description of the way the Samoyeds capture the Brent Goose whilst it is incapable of flight. Instinctively aware of their helplessness, the Geese endeavour to get to the sea, and on it congregate in large flocks, until their quills have grown. But the Samoyeds cleverly surround them—often taking advantage of a dense sea-fog to do so—and quietly drive them into a netted enclosure on the shore, where they are killed at leisure. One of these grand “drives” witnessed by Mr. Trevor-Battye resulted in the capture of upwards of three thousand Brents! A form or variety of the Brent Goose, with the under parts below the breast nearly white, is commonly found consorting with birds of the typical colour. It is the _Bernicla glaucogaster_ of Brehm, and, as far as is known, breeds only in the Nearctic region. It is not known to differ in its habits from the more typical form.