142 BIRDS 



is larger than the female, and generally has the tubercle 

 better developed. The feet of the common form are black, 

 but in a variety known as the Polish Swan, which appears 

 to have arisen by mutation, the feet are leaden gray. The 

 young of this bird are white when hatched, while those of 

 the typical Mute Swan are sooty gray. 



These birds are bred in Europe with the greatest facility, 

 but it is only of very recent years that much success has been 

 attained in this country. Many have explained the failure 

 by the belief that the males were rendered sterile before 

 leaving Europe. Whatever the difficulty, it seems to have 

 been overcome, and Mute Swans are now being bred here 

 in some numbers. 



At Belmar, New Jersey, a flock of nine birds has been 

 bred up to more than fifty in the last five years. The birds 

 are kept on a large lake in the center of the town. This 

 lake is well supplied with Anacharis, an aquatic plant of 

 rank growth. The original intention was that the swans 

 should prevent the overgrowth of this plant, which they 

 appear to be doing with great success. The birds nest 

 about the shores of the lake, not far removed from public 

 highways and entirely without shelter. The scene during 

 the breeding season is one calculated to stir the enthusiasm 

 of the most phlegmatic nature-lover. 



Male swans are exceedingly pugnacious, particularly dur- 

 ing nesting time, and will not tolerate the presence of a 

 rival or another pair in the immediate vicinity. Even a 

 man must be on his guard when near the nest, for a blow 

 of the wing of a swan is not to be taken lightly. 



The nest is built of sticks and rubbish and is a structure 

 of considerable size. The eggs number from three to seven, 

 and are greenish-white in color. Incubation occupies six 

 weeks, and the young of the typical form, as already men- 

 tioned, are sooty gray. If plenty of green food is avail- 



