198 THE NESTS AND EGGS OF 



generally made in a large and lofty tree, on a flat 

 horizontal branch, or in a fork near the trunk, but some- 

 times it is built in a cleft of the rocks or on the cliffs. 

 Occasionally it has been known in a tree on the old nest 

 of a White-tailed Eagle. It is a ponderous structure 

 from four to six feet across, very flat, and made chiefly 

 of sticks of all sizes and thicknesses. The cavity con- 

 taining the eggs is very shallow, and lined with tufts of 

 green moss. This lining is renewed each year. The 

 bird is a close sitter, especially when incubation is far 

 advanced, and when flushed rises into the air and wheels 

 round and round above the tree, anxiously awaiting the 

 fate of the nest, usually being joined by its mate. 



Range of egg colouration and measurement : 

 The eggs of the Black Stork are from three to five in 

 number. They are rough in texture, porous, with little 

 or no polish, and pure white. Average measurement, 

 26 inches in length, by 2"0 inches in breadth. Incubation, 

 performed chiefly, if not entirely, by the female, lasts 

 about a month. 



Diagnostic characters : The eggs of the Black 

 Stork are smaller than those of the White Stork, and 

 when empty and held up to the light are green inside, 

 those of the latter bird being yellowish-white. 



