VOL. ix.J ON INCUBATION. 113 



though the Gull was certamly domg aU it could to guard 

 them. It is the actual covering of the eggs by the bird 

 sitting on them that saves them, for with birds it is 

 undoubtedly largely a matter of '''' out of sight, out of 

 mind." This is clearly shouii by the success achieved 

 l)y the method of protecting eggs by covering them witli 

 down or vegetation, as Ducks and other species do. How 

 effective the covering of eggs is was accidentally shown 

 in the case of one of the Gulls' nests moved from its 

 origmal site. It was soon found and one egg devoured. 

 In the process the contents of the first egg was smeared 

 over the other, and pieces of the vegetation forming 

 the nest adhered to it. This egg was left untouched, 

 though the egg-sucker had it under its eye while 

 devouring the first, the accidental covering through 

 vegetation adhering to the egg having saved it. The 

 egg was not beneath the nest material, the leaves, etc., 

 were merely stickmg to its surface. 



THE COVERING OF EGGS CONSIDERED IN REI ATION TO 

 THE OVITEGOL^S HABIT. 



Ducks, Geese, the Partridge, and some other species 

 which lay conspicuous eggs, preserve them by covering 

 them with down or pieces of vegetation. This habit 

 may be briefly considered m relation to the significance 

 of birds incubating from the laymg of the first egg. 



The case of the Canada Goose {B. canadensis) and 

 White Pelican (P. erythrorhynchos) may be taken as an 

 example. These birds lay white eggs of approximately 

 the same size. The Goose makes its nest in solitude, 

 sometimes hidden in the bush, but also frequently on 

 the exposed shores of islands, and protects its eggs by 

 covering them with dowai. If the birds did not cover the 

 eggs, in all probability few eggs would be left to hatch, 

 for the Crows take toll of the nests of this species as it 

 is, probably finding them when the Geese are off feeding 

 after incubation has commenced, for under these circum- 

 .stances the eggs are not always covered. 



