GREAT NORTHERN-DIVER 447 



while in North America, though some nests are mere depressions in 

 the gravel, a heap of dead vegetable matter, sedge, weeds, bulrushes, 

 etc., is occasionally made near the shore. The normal clutch consists 

 of two eggs, rather elongated in shape, and varying in ground-colour 

 from deep chocolate-brown to some shade of olivaceous or brownish, 

 sometimes without markings and at other times spotted and blotched 

 sparingly with black and a few light inky shellmarks. Average size of 

 64 eggs, 3'56 x 2'28 in. [90*5 x 58 mm.]. It is said that three eggs have 

 occasionally been found in a nest in North America, and in several cases 

 a single egg has been found highly incubated. Both sexes take part 

 in incubation, but observations on this point are not easily made, for 

 long before the nest is reached the sitting bird, warned by her mate, has 

 slid down into the water and disappeared. A minute later her head 

 and back show above the still water of the lake, as she quietly dips 

 her bill in the water, and then raising it apparently sips a few drops. 

 Then we realise that her mate is also present not far away, having 

 suddenly appeared in the same mysterious way. Then even as we 

 watch them, one of the pair vanishes without the slightest apparent 

 effort. In this case the eggs are nearly fresh, so that the parents show 

 little anxiety, but when they have been incubated some time they will 

 come within fifty yards of the observer. 



All the Divers seem to have at least two distinct classes of notes : 

 there is a loud wail, often uttered on the wing, and there is also a 

 conversational note or series of notes, usually heard when both are 

 together on the water. This latter sounded to me like a deep loud 

 note, followed by three high-pitched ones, " yooo, wee wee wee." Perhaps 

 it is this which Mr. Blake Knox writes as a loud, hoarse and piercing 

 cry, "gan-a-ece," the first syllable deep, the last like a scream. Quite 

 distinct from this is the loud resonant " fiooo-hoo-hoo-koo," which I have 

 heard echoing over the waters of the lake. This is evidently the note 

 which is given in Naumann's work as " htthithuhu" etc., or "uhuuuu," 

 and is described by Messrs. Pearson as " a peculiar and rather pleasing 

 trumpeting note." It must, however, be distinct from the blood- 



