IO6 LAKES AND RIVERS. 



instead of black and white, and the collars round 

 the neck are indistinctly marked until the third year. 

 The bird lays only one egg, dark olive-brown with 

 black spots ; it is about the size of those of the 

 domestic goose. It utters a loud, discordant sound. 

 It is perhaps the finest and most imposing of the 

 water-fowl, whether we consider its size or the beauty 

 of its markings. The feathers lie very thick and 

 close, and under the skin is a layer of fat of unusual 

 thickness in sea-fowl. Thus protected it enjoys a 

 uniform temperature, which is fitted to maintain its 

 large body in health, exposed as it is to the cold of 

 the Northern sea. 



The Black-throated Diver (Colymbus Arcticus) is 

 a rare visitor to Britain. It breeds .n Sutherland 

 on the fresh- water lakes. " It was in the summer of 

 1834," says Mr. Hewitson, " during an excursion to 

 explore the zoological productions of the county of 

 Sutherland, that Mr. Selby was rewarded by discover- 

 ing this beautiful species breeding upon most of the 

 inland lochs. The eggs, which are two in number, 

 were first found upon a small islet at the bottom of 

 Loch Shin ; they were upon the bare ground, and at 

 about 10 or 12 feet from the water's edge. The 

 bird was observed by Sir William Jardine, who formed 

 one of the party, whilst in the act of incubation, and 

 was seated upon its eggs in a horizontal position, and 

 not upright like the cormorant, shag, and guillemot ; 

 and whilst still in this position it thrust itself forward 

 when disturbed, and had thus worn with its breast a 

 distinct track to the margin, whilst launching itself 

 boat-like into the lake. We did not see this species 



