172 THE ZOOLOGIST. 



is necessary to remember that such nests are nearly always 

 partially covered by overhanging leaves and branches, by a pro- 

 jection of rock or stone, by thick herbage, or by sedges and long 

 grasses. This fact will often account for the deeper or paler 

 shades of egg-colouring. 



I. Eggs laid in open nests are coloured. 



(a) The ground colour of those laid in trees and bushes is 

 often some shade of green or blue marked with brown, red, or 

 black, e.g. Thrushes, Finches, Crows. 



(b) When the nest is placed very low down amongst herbage, 

 or when it is placed in a covered site, the ground colour of the 

 eggs is paler, and so are the markings, which are sometimes 

 greenish, e.g. Kedbreast, Wagtail, Whitethroat ; but not so the 

 Pipits. 



(c) When exposed to some extent on the ground they are 

 generally clay-colour, or brown, or greenish brown, spotted and 

 blotched with a darker shade, or even with black, e.g. the Lark, 

 Lapwing, Curlew, Gulls. 



(d) Certain birds, as Ducks, Partridge, Grebes, cover their 

 eggs when they leave the nest. Such eggs are usually white or 

 of a pale tint. This might be expected, as the protection of 

 colour is in such cases unnecessary. 



(e) Large birds which are able to defend themselves may be 

 expected to be capable of keeping their eggs safe from the attacks 

 of Crows, &c. Swans and Cormorants will come under this head. 



II. Birds which nest in holes nearly always have white eggs, 

 e.g. Swift, Woodpecker, Kingfisher, Paffin, Petrel. But very 

 small birds so nesting generally lay white eggs speckled with red. 



The only exceptions which occur to me are the Wheatear, 

 Redstart, Starling, Jackdaw, and Chough. The first two of 

 these have already been dealt with. I have no personal know- 

 ledge of the Chough. But there is some reason to suppose that 

 nesting in holes is a comparatively recent habit both with the 

 Starling and the Jackdaw. In 1887 I found two Starlings' nests 

 which were "open." One was at the top of a spruce-fir, built 

 upon an old Wood-Pigeon's nest ; the other was in ivy. Perfectly 

 fresh-laid Starlings' eggs differ very much, varying from a 

 decided blue to nearly white. Jackdaws sometimes lay their 

 eggs in hollow trunks, where they can be seen from above. 



