146 ANATIDE. 



The young of the year in August liavc the beak flesh 

 colour ; the head and neck brown ; chin and front of the 

 neck white ; interscapulars and wings brown ; wing-coverts 

 white ; tertials white, but edged with chesnut, the first 

 appearance of that colour ; primaries black ; speculum be- 

 coming green ; all the under surface white ; legs flesh colour. 



The young birds do not breed till they are two years old. 



I referred, at page 55 of the present volume, to the 

 })eculiar character of the organs of voice in some of the Geese 

 and Swans, and in almost all the Ducks and Mergansers, 

 forming together the large, the valuable, and interesting 

 fomily of the Anatid?c ; and I may here refer particularly 

 to that organ as found in the Shieldrake, which is so entirely 

 distinguished from that of any other species, as at once and 

 alone to afford, as far as I have yet seen, a decided specific 

 character. The trachea, or windpipe, in the Shieldrake is 

 about ten inches long, nearly uniform in size throughout its 

 length, except towards the bottom, where, for about one 

 inch, it is much smaller. On each side of the bone of divari- 

 cation, forming the bottom of the tube, there is a globular, 

 hollow, bony protuberance, that on one side being as large 

 again as the one on the other. The bone is thin, and so 

 flexible when in its moist and natural state as readily to 

 become indented on pressure. The representation given 

 below is only a little smaller than the natural size. The 

 tube below each enlargement, going off, one to each lobe of 

 the lungs, presents nothing remarkable. 



■M^a 



