246 ERGUS SERRATOR. 



narrow bands of black ; primaries, black ; secondaries, 

 white; several of tbe latter edited with Mack; lower 

 part of the back, the rump, and tail-coverts, gray, 

 speckled with black; sides under the wings, elegantly 

 crossed with numerous waving lines of black ; belly 

 and vent, white; legs and feet, red ; the tail, dusky 

 ash ; the black of the back passes up the hind neck in 

 a narrow band to the head. 



The female is twenty-one inches in length, and thirty 

 in extent ; the crested head and part of the neck are of 

 a dull sorrel colour ; irides, yellow ; legs and bill red, 

 upper parts, dusky slate; wings, black ; greater coverts, 

 largely tipt with white ; secondaries, nearly all white ; 

 sides of the breast, slightly dusky ; whole lower parts, 

 pure white; the tail is of a lighter slate than the hack. 

 The crest is much shorter than in the male, and some- 

 times there is a slight tinge of ferruginous on the breast. 



The windpipe of the male of this species i- 

 curious,and differs something from that of the goosander. 

 About two inches from the mouth, it swells out to four 

 times its common diameter, continuing of that size for 

 about an inch and a half. This swelling is capable of 

 being shortened or extended; it then continues of its 

 first diameter for two inches or more, when it becomes 

 flattish, and almost transparent for other two inches ; 

 it then swells into a bony labyrinth of more than two 

 inches in length by one "and a half in width, over the 

 hollow sides of which is spread a yellowish skin like 

 parchment* The left side of this, fronting the back of 

 the bird, is a hard bone. The divarications come out 

 vei v regularly from this at the lower end, and enter 

 the lungs. 



The intention of Nature in this extraordinary struc- 

 ture is probably to enable the bird to take down a 

 supply of air to support respiration while diving; yet 

 why should the female, who takes the same submarine 

 excursions as the male, be entirely destitute of this 

 apparatus ? 



