NOX-LYDIGENOUS BRITISH BIRDS. 215 



Dybowski, on the rocky banks of a river. It is a slight 

 structure, a mere hollow trodden in the ground, and lined 

 with a few bits of herbage. Nests described by Dybowski 

 are said to have been made of small stones fitting close to 

 each other, the surface being flat, and deepening towards 

 the centre. I have found nests of the Fulmar very similar 

 in construction. The parent birds are very wary at the 

 nest, one being stationed near by to give the alarm of 

 approaching danger, when the sitting bird slips quietly 

 away, running or walking for a little distance, then taking 

 flight. They are very pugnacious, and beat off any 

 predaceous bird or animal with considerable courage. 



Range of egg colouration and measurement : 

 The eggs of the Demoiselle Crane are two in number. 

 They vary from pale buff to olive-brown in ground colour, 

 spotted and blotched with umber-brown, and with under- 

 lying markings of lilac-gray. Two very distinct types 

 occur, one in which the surface spots predominate, the 

 other in which the underlying markings are most numer- 

 ous and conspicuous. Average measurement, 3"5 inches 

 in length, by 2'0 inches in breadth. Incubation, per- 

 formed by both sexes, lasts about a month. 



Diagnostic characters : The eggs of the Demoiselle 

 Crane cover much the same range of colour variation as 

 those of the Common Crane, but may always be dis- 

 tinguished from those of that species by their much 

 smaller size. 



