76 THE NESTS AND EGGS OF BRITISH BIRDS. 



Externally it is made of dry grass, sea-weed, and dry 

 scraps of marine vegetation ; sometimes moss is almost 

 exclusively used ; internally it is lined with finer grass 

 and horsehair, wherever such can be obtained. I once 

 found a nest of this species at the Fame Islands con- 

 taining one large white Gull's feather in the lining. At 

 St. Kilda the birds pull the Puffin snares to pieces to 

 obtain the horsehair. The whole structure is loosely 

 put together, but the inside is neatly arranged. The 

 Rock Pipit is a close sitter, but when scared from the 

 nest both parents frequently flit up and down in a 

 very restless, anxious manner. 



Range of egg colouration and measurement: 

 The eggs of the Rock Pipit are four or five in number. 

 They vary in ground colour from pale greenish-gray to 

 pale brownish-gray, or nearly white, mottled, spotted, 

 and blotched with olive-brown or reddish-brown, and 

 with underlying markings of grayish-brown. On some 

 eggs a few dark brown lines or streaks occur, usually at 

 the larger end. The markings are generally pretty 

 evenly distributed over the entire surface ; but occasion- 

 ally they are most numerous, and form a zone round 

 the larger end of the Q.g%, and sometimes they are fewer 

 and larger. Average measurement, "85 inch in length, 

 by •63 inch in breadth. Incubation, performed chiefly 

 by the female, lasts thirteen or fourteen days. 



Diagnostic characters : The large size and brown 

 appearance of the eggs of the Rock Pipit, combined 

 with the situation of the nest, serve to distinguish them 

 from those of other British species most likely to be 

 confused with them. 



