THE COMMON TERN. 411 



dry places, frequently upon uninhabited islands, or remote 

 parts of such as are inhabited. They make no formal nest, 

 but merely level the sand a little, or simply deposit their 

 eggs on the bare rock. These are usually two in number, 

 pale olive brown, with dusky patches. 



The numbers of these birds that are scattered over the 

 northern parts of the Atlantic are very great ; and those 

 dry and comparatively low islands and holms, as they are 

 styled in the north, that are suitable for their breeding, 

 are in the season so thickly covered with their eggs, 

 that it is difficult to walk without breaking them. ; and 

 the wheeling in the air, tumbling along the ground, and 

 wailing and screaming, which they make when one meets 

 them in breeding 1 time, are very remarkable. The eggs, 

 placed on the sand or shingle, are, when the weather is dry 

 and warm, left in part to be hatched by the action of the 

 sun ; at least, in such weather, the birds do not sit during 

 the day. They are then abroad feeding j and it is not easy 

 to imagine how so many as are huddled together upon the 

 same spot, can find food within the range even of a tern's 

 flight. But they do find ifc, and that too at no great dis- 

 tance ; for the instant that one lands, though the eggs are 

 all warmed, the cloud of birds are instantly wailing in the 

 air. Before the dew begins to fall, they return and sit, and 

 if it rains, they sit during the day. It is a great advantage 

 to these birds that they hatch on the bare earth that their 

 food comes out much more abundantly on those days when 

 one of the pair must keep the nest. How each knows her 

 own eggs, and her young after they are hatched, in such a 

 multitude, and all so much alike, is a matter that human 

 speculation cannot fathom : but they do know ; for after the 

 young have grown a few days, the parents do not alight and 

 feed them with the bill, but fly over them with a twitch, and 

 drop the food into the bills, with the most unerring certainty, 



