288 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



"On August 6, 1833, Mr. John W. Audubon found a nest of this Falcon 

 among some rocky cliffs near Bras d'Or, Labrador, containing four young birds 

 ready to fly, two of which were secured. The nest was placed among the 

 rocks about 50 feet from their summit and more than 100 feet from their 

 base. It was composed of sticks, seaweed, and mosses, was about 2 feet in 

 diameter, and almost flat. Its edges were strewed with the remains of their 

 food, and beneath the nest was an accumulation of the wings of the Ptarmigan, 

 Mormons, Urise, etc., mingled with large pellets of fur, bones, and various 

 substances." l 



Four eggs seem to be the number usually laid by this Falcon, and 

 they are deposited about the middle of May. The shells of these eggs are 

 roughly granulated and without luster. In shape they are ovate, and appar- 

 ently indistinguishable from those of the preceding subspecies; the set under 

 consideration, and the only one in the U. S. National Museum collection, is a 

 trifle lighter colored. 



The ground color is a creamy white nearly hidden by fine irregular 

 markings of light reddish or rusty brown. Three of the specimens are thus 

 marked; in the fourth and lightest colored one these markings are more of a 

 clay color, with scarcely a trace of red. They all differ slightly in color from 

 each other. 



The measurement of these eggs is as follows: 58 by 45.5, 58 by 44.5, 

 57.5 by 45, and 57 by 45.5 millimetres. 



The type specimen, No. 22389 (PI. 10, Fig. 1), was collected near Fort 

 Chimo, Labrador, May 22, 1883, by Mr. L. M. Turner, U. S. Signal Service. 



97. Falco mexicanus SCHLEGEL. 



PRAIRIE FALCON. 



Falco mexicanus SCHLEGEL, Abhandlungen aus dem Gebiete der Zoologie, 1841, 15. 



(B 10, C 342, R 413, C 502, U 355.) 



GEOGRAPHICAL RANGE : Western United States, from eastern border of the Great 

 Plains to the Pacific, south into Mexico ; casual eastward to Illinois. 



The breeding range of the Prairie or Lanner Falcon includes the more 

 open country from eastern Texas in the vicinity of Houston, where Nehrling 

 reports it as resident but not common, north through the Indian Territory, 

 Kansas, northwestern Missouri, and Nebraska to South and North Dakota, 

 which seems to form the northern limit of its breeding range, as far as known 

 at present. Prof. J. Macoun has taken it at Rush Lake, Northwest Territory, 

 in latitude 51, and it probably occurs and breeds in small numbers along the 

 southern border of the Dominion of Canada from western Manitoba to southern 

 British Columbia. From the Dakotas it reaches westward through the interven- 

 ing States, excepting the densely timbered and higher mountain regions, to the 



1 History North American Birds, 1874, Vol. HI, p. 121. 



