476 BRITISH BIRDS. 



CYGNUS OLOR. 

 MUTE SWAN. 



(PLATE 57.) 



Anser cygnus, Briss. Orn. vi. p. 288 (1760). 



Anas cygnus, Linn. Syst. Nat. i. p. 194 (1766, partitn). 



Anas cygnus, ft. mansuetus, Linn. Syst. Nat. i. p. 194 (17(36). 



Anas cygnus mansuetus, Tunst. Orn. Brit. p. 4 (1771). 



Anas olor, Gmel. Syst. Nat. i. p. 501 (1788) ; et auctorum plurimorum Tem- 



minck, (Naumann), (Dresser}, (Saunders}, &c. 

 Cygnus gibbus, Bechst. Naturg. Deutschl. iii. p. 815 (1809). 

 Cygnus olor (Gmel.}, Vieill N. Diet. tfHist. Nat. ix. p. 37 (1817). 

 Cygnus sibilus, Pall. Zoogr. Rosso-Asiat. ii. p. 215 (1826). 

 Cygnus mansuetus (Linn.}, Flem. Brit. An. p. 126 (1828). 

 Cygnus immutabilis, Yarrett, Proc. Zool. Soc. 1838, p. 19. 

 Cygnus olor immutabilis, SMeg. Rev. Crit. p. cxii (1844). 

 Cygnus unwini, Hume, Ibis, 1871, p. 413. 



It would be difficult to prove that the Common Swan, often erroneously 

 called the Mute Swan, is a British bird. It is said to have been intro- 

 duced from Cyprus in the twelfth century, and is now found in a state of 

 semidomestication on rivers, canals, lakes, ponds, and ornamental waters 

 in most parts of our islands. It may, however, readily be believed that 

 a bird which migrates regularly to breed in Denmark and North Germany 

 must occasionally wander as far as our shores. Most, if not all, writers on 

 British birds have given it the benefit of the doubt, though it has never 

 been, known to breed in a wild state in any part of Great Britain or 

 Ireland. 



The Mute Swan has a very restricted range. It is doubtful whether in 

 a wild state it breeds west of the Rhine, and north of the Baltic it only 

 breeds in Denmark and South Sweden, being only an accidental visitor to 

 Norway. It is a summer visitor to South Russia, the valley of the Danube, 

 Transylvania, and Greece, but in the basin of the Mediterranean it is 

 principally known as a winter visitor. It is a summer visitor to the 

 northern shores of the Caspian, to Turkestan, and to Mongolia, occasion- 

 ally straying into Dauria, where it was observed by Radde. It winters in 

 the southern portions of the Caspian, occasionally wandering into the 

 extreme north-west of India. 



In the northern portion of its range the Swan is a migratory bird, 

 arriving at its breeding-grounds in March and leaving them again in 

 October. It migrates in flocks or small parties, and may be seen winging 

 its way northward in early spring during the day ; but it also migrates by 

 night, and the rush of its wings may often be heard when it is too dark to 



