PARENTAL AFFECTION IN THE SWAN. 253 



the sternum for the reception of the trachea, which is admirably 

 described by Mr. Yarrell as descending the passage between the two 

 branches of the forked bone called the merrythought to a level with 

 the keel of the breast-bone, which is double, and receives the tube of 

 the trachea between its two sides, which here turns upon itself after 

 traversing the whole length of the keel, and passes upwards and 

 forwards, and again backwards, till it ends in the vertical bone where 

 the two bronchial tubes go off, one to each lobe of the lungs. This 

 is the apparatus through which the cry is produced, which is variously 

 described as a whistle, a whoop, or a song, according to the fancy of 

 the writer. They fly at a great height when on a migratory journey, 

 and in a wedge-like figure, uttering this note as they proceed, and 

 when heard at a distance it is not unmusical. Mr. McGillivray listened 

 to a flock of wild swans coming in from the Atlantic after a gale ; 

 their clear, loud, and trumpet-like cries delighted him as they sped 

 their way in lengthened files ; but they were too far off for him to 

 decide whether or not they were of this species. 



The female lays from six to eight eggs, of a greenish white, and 

 the incubation lasts about six weeks. The cygnets are at first covered 

 with a grey down, and do not put on their adult plumage until the 

 third year. Swans care but little for concealing their broods, as they 

 feel confident of their power to protect them against every enemy. 

 They will fight even with the Eagle itself, harassing it with beak and 

 wings, until the marauder is glad to make a more or less honourable 

 retreat. 



In the protection of their young they display extraordinary courage. 

 On one occasion a female swan was sitting on the bank of a river, 

 when she perceived a fox swimming towards her from the opposite 

 bank. Thinking that she would be better able to defend herself in her 

 natural element, she took to the water and went to meet the enemy 

 which was threatening her brood. She soon reached him, and, spring- 

 ing upon him with much fury, gave him such a violent blow with her 

 wing that the fox was disabled, and consequently drowned. 



The male swan is equally attentive with the female to the brood, 

 and watches them with a rare devotion. He carries them about on 

 his back, takes them under his wings to warm them, and never 

 abandons them while they are still young. It is a beautiful sight to 

 see him gliding over the water at the head of his young flock, 

 looking forward with an inquisitive eye, and quite prepared to sweep 

 away any opposing obstacle ; whilst the mother keeps some distance 

 behind, ready to protect the rear. How much, too, are they to 

 be admired as they sail majestically along over the surface of some 



