The Black-throated Divers that breed with us, retire to their inland haunts in May. Its favourite nesting places are on islands in moorland lochs, pools, and tarns. It displays few social tendencies at this season, although several pairs not unfrequently nest within a comparatively small area of exceptionally suitable country, each, nevertheless, keeping to its own particular haunt. This Diver may also pair for life, seeing that it evinces considerable attachment to certain favourite nesting places. The nest is always made upon the ground, and seldom very far from the water, to which the frightened bird can retire readily. An island covered with short herbage is always preferred in Scotland, but in some places the bare shingly beach is selected. This nest, often of the slightest construction, is made of stalks of plants, roots, and all kinds of drifted vegetable fragments, lined with grass. Sometimes no nest whatever is made. The two eggs are narrow and elongated, olive- or rufous-brown, sparingly spotted and speckled with blackish-brown and paler brown. The sitting bird is ever on the alert to slip off into the water at the first alarm; and sometimes both birds will fly round and round in anxiety for the fate of their treasured eggs. A movement seawards is soon taken when the young are sufficiently matured. This Diver has a wide geographical range outside our limits, extending across Europe and Asia to Japan and North-west America, perhaps as far as Hudson Bay. American authorities, however, insist upon the specific distinctness of most of the Black-throated Divers found in Alaska, and have named this form _C. pacificus_. RED-THROATED DIVER.