214 



WHITE GRYFALCON 



353. Fa Ico islamlus. 23 in. 



Adults in perfect plumage, pure white, slightly barred 

 on the back and spotted below with black. 



Nest. Of sticks, lined with grasses and feathers; 

 placed on ledges of cliffs; eggs bulky white, specked 

 with reddish brown, often so thickly that the ground 

 color is obscured (2.30x1.80). 



Range. Arctic region, breeding in Northern Green- 

 land, and wintering to the Gulf of St. Lawrence, and 

 casually to northern Maine. 



GRAY GYRFALCON 



354. Falco rusticolus. 23 in. 



Adults white, heavily barred above, and streaked be- 

 low with gray and black. 



Range. Arctic regions, south in winter, rarely to 

 northern United States. 



354a. GYRFALCON (F. r. gyrfalco). Similar to the 

 ast but darker, the latter being usually more white than 

 dusky, while this is the reverse. 



354b. BLACK GYRFALCOX (F. r. obsoletus). Much 

 darker than the last, the markings tending to be buffy 

 white spots on a grayish black ground. 



