BIKDS or INDIANA. 623 



Mr. Robert Ridgway calls attention to the fact that while the males 

 of this species and the last may readily be distinguished, according to 

 the characters specified, it is difficult to give constant characters by 

 whieh the females of these two species can be infallibly determined. He 

 says: "The examples, which are known to represent G. islandica differ 

 from the positively determined females of G. clangula americana in 

 the following respects: (1) The color of the head and upper half of 

 the neck is considerably darker, being a rich sepia or snuff-brown, 

 rather than a grayish brown; (2) the greater wing coverts are distinctly 

 tipped with black, forming a conspicuous dusky stripe between the 

 two larger white areas of the wing, which in G. clangula americana are 

 (usually at least) merged into one continuous space. 



"Further than this we find no distinction, while indeed some exam- 

 ples are decidedly intermediate in both respects, as to render it quite 

 uncertain to which species they belong of the two characters named. 

 However, the color of the head seems for the most constant, and may, 

 perhaps, be found quite distinctive." (Birds of Illinois, Vol. II, pp. 

 169, 170.) 



21. GENUS CHARITONETTA STEJNEGER. 



4I 1 . Nostril nearer base than tip of bill ; more or less white behind the eye, none 

 in front; head of male very puffy. C. albeola (Linn.). 46 



46. (153). Charitonetta albeola (LINN.). 



Buffle-head. 

 Synonyms, BUTTER DUCK, BUTTER BALL, SPIRIT DUCK. 



Adult Male. Head and upper neck glossy green, bronze and purple; 

 a band of white extending from eye to eye across the back of head; 

 lower neck, lower parts, speculum, wing, coverts, and outer scapulars 

 pure white; rest of upper parts black. Adult Female. Head, neck and 

 upper parts generally, dusky grayish-brown; a spot behind each eye, 

 speculum and lower parts, white. 



Length, 14.25-15.25; wing, 6.75-6.90; bill, 1.10-1.15; female, 

 smaller. 



RANGE. North America, breeding in Iowa and Maine and that lati- 

 tude, through the fur countries, and northward to Alaska. Winters 

 from Michigan to Cuba and Mexico. 



Nest, in hollow tree. Eggs, 6-14; dull light buff; 1.98 by 1.46. 



Common migrant and winter resident. Some winters they are pres- 

 ent throughout the entire State; others when the northern streams and 

 lakes are ice bound they are only found along the southern border. 



