82 GEOGRAPHICAL DISTRIBUTION 



Strix bracliyotus. 

 Anas clypeata. 

 Sterna arctica. 

 Fidigula clangula. 

 Strepsilas interpres. 



The breeding range of the three following species is not only 

 arctic, but also Kubarctic and subtropic : they all breed within the 

 limits of the British Islands : 



Corvus corax. 

 Aquila chrysaetus. 

 Cotyle riparia. 



The breeding range of the eight following species extends to 

 both the subarctic and subtropic divisions of the Temperate 

 Kegion. The two first named breed in some numbers within the 

 limits of the British Islands, the three next more locally, and it is 

 supposed that the sixth occasionally does so : 



CertJiia familiaris. 

 Anas boschas. 

 Anas strepera. 

 Pandion haliaetus. 

 Procellaria leachi. 

 Podiceps cornutus. 

 Podiceps rubricollis. 

 Anthus spinoletta. 



The breeding range of the three following species is not only 

 subarctic and subtropic, but is also tropic. The first mentioned 

 breeds commonly within the limits of the British Islands, the next 

 used locally to do so in small numbers, but the last has not been 

 found breeding on our coasts : 



Aluco flammeus. 

 Sterna dougalli. 

 Sterna caspia. 



The breeding range of one species may be regarded as sub- 

 tropic and tropic 



Ardca nycticorax. 



