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Mr. Lawrence's types, and compared a series of specimens, he has convinced himself that the 

 Pacific bird cannot be treated as a good species, as it differs but in size, and is merely the 

 extreme link of an unbroken chain. 



In habits the Black-throated Diver closely assimilates to its allies the Great Northern and 

 Red-throated Divers ; and, like those, it swims with great speed, dives with ease, often remaining 

 for some time below the surface ; and when flying, it advances with great rapidity in a direct 

 course, having its long neck outstretched, and propelling itself with quick beats of the 

 wings. During the winter season this bird is usually seen off the coast, and but seldom on 

 inland lakes or rivers ; but during the breeding-season it resorts to inland sheets of water for the 

 purpose of nidification. Its cry, like those of its allies, is strange and weird ; and the passing 

 traveller is often startled by it as it reechoes through the wild localities where it is found. 

 Mr. Robert Gray says that the natives of Benbecula and North Uist compare it to the words 

 Deoch ! deoch ! deoch ! thcCn loch a traoghadh, which may be interpreted as " Drink ! drink ! 

 drink! the lake is nearly dried up." 



When swimming at its ease, this Diver floats with a good deal of the body exposed to view ; 

 but directly it perceives that it is noticed, it gradually sinks itself below the surface until only 

 the head and neck are exposed, and propels itself with great speed out of reach of danger. 

 When fired at, it will dive at the flash, and thus frequently escape unscathed, remaining not 

 unfrequently for nearly two minutes below the surface, and reappearing at a considerable distance 

 from the place where it disappeared. 



For the purpose of nidification it selects a small islet or a spit of land protruding into the 

 lake, and usually close to the water's edge ; and there is always a visible track from the water's 

 edge to the nest, caused by the shuffling mode in which the bird progresses on land. Captain 

 Elwes writes respecting its nidification in Scotland as follows : — " The Black-throated Diver 

 sometimes lays its eggs as early as May 9th, though I have found them fresh six weeks later ; 

 and if the first pair are taken, it always lays again in the vicinity of the first nest. I have even 

 heard of a fifth egg having been laid after the second pair were taken. They are not found on 

 the small lochs to which the Red-throated Diver retires to lay, but on large pieces of water 

 containing several islands. In one of these islands, where the shore is soft and shelving, the bird 

 creeps up about a yard from the water and lays two eggs on a bare round spot as large as a 

 dinner-plate, sometimes placing a few bits of grass or rush round them, and always making a 

 visible track to the water by the pressure of her breast. When disturbed by the approach of 

 any one, she dives quietly off the eggs and comes up at a little distance, but is very unwilling to 

 leave the place altogether. They are found in scattered pairs nearly all over the West High- 

 lands, though I do not think they breed in Skye, Mull, or May. In winter they are not often 

 seen, and are difficult to distinguish from the Great Northern Diver." 



Mr. Collett writes to me, " In Norway, as soon as the lakes begin to get clear of ice, which 

 is usually early in May, the present species reappears at its breeding-haunts, which it had left in 

 the preceding September. Like the Red-throated Diver it often collects in flocks during the 

 seasons of passage ; and in the middle of May I have observed flocks numbering as many as 

 eighty individuals passing over the Christiania fiord. The eggs of the Black-throated Diver, 

 usually two, but sometimes only one in number, are deposited close to the water's edge, so that 



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