SHAG. 219 



an islet or reef, or on a ledge of the cliff's, usually where 

 the rocks overhang considerably. The nests are bulky 

 structures, wherever the sites admit of elaborate build- 

 ing, composed externally of sticks, stalks of plants, and 

 sea-weed, and lined with straw, coarse grass, and turf, 

 all more or less matted together with droppings, decay- 

 ing fish, and slime. Many nests are enlarged and 

 patched up, season by season. The birds sit more 

 closely than Cormorants usually do, many not leaving 

 their nests until absolutely compelled. I have often 

 had actually to drive this species from its eggs. 



Range of egg colouration and measurement : 

 The eggs of the Shag are usually three in number, 

 sometimes four or even five, but more often two. They 

 are elongated, and the shell is of a delicate green, where 

 it is visible through the more or less thick coating of 

 lime. Average measurement, 2'5 inches in length, by 

 I "5 inch in breadth. Incubation, performed by both 

 sexes, lasts about a month. The eggs are usually sat 

 upon as soon as laid. 



Diagnostic characters : As a rule the eggs of 

 the Shag may be distinguished from those of the Cor- 

 morant by their smaller size, but the rule unfortunately 

 is not absolute, consequently the eggs require careful 

 identification. The situation of the nest is of some 

 service in the matter of identifying them. 



