174 NESTS AND EGGS OP 



with many shades of red and brown ; some are faintly marked here 

 and there with a light purplish tint, and again the colorings may form 

 an almost confluent wreath at either end. The largest eggs in Mr. Nor- 

 ris' collection measure 2.41x1.84, 2.37x2.00 ; the smallest, 2.17 x 1.80, 

 2.20 X 1.78. The average size is 2.36 x 1.80. 



337a. Buteo borealis kriderii Hoopes. [436a.] 



Krider's Ha-nrb. 



Hab. Great Plains of the United States, from Minnesota to Texas. 



This lighter colored variety of the Red-tailed Hawk occurs in the 

 Great Plains, from Minnesota to Texas ; east irregularly or casually 

 to Iowa and Northern Illinois. 



Mr. F. M. Dille writes that this bird nests in remote places on the 

 plains and among the large cliffs of Colorado. He was unable to de- 

 tect any difference between the nest and eggs of this bird and those of 

 the Western Red-tail. He took a set of the eggs, three in number, in 

 Weld county, May 24, 1886, from a nest in a Cottonwood tree. They are 

 now in the collection of J. Parker Norris. Two of these specimens 

 are slightly spotted with Vandyke brown, but the third is quite heavily 

 splashed and blotched at the smaller end with chestnut and cinnamon ; 

 their sizes are 2.34 x 1.82, 2.30 x 1.84, 2.28 x 1.83. 



Mr. Dille states that the nest contained cotton balls, from the tree 



in which it was placed ; these had burst and made excellent soft lining 



for the nest. 



337(5, Buteo borealis calurus (Cass.) [436^.] 



Western Red-tail. 



Hab. Western North America, especially in the United States, from the Rocky Mountains to the 

 Pacific, south into Mexico. 



A blackish or sometimes an almost entirely sooty variety inhabit- 

 ing Western North America. In all respects its breeding habits are 

 the same as those of the Eastern representative, nesting in the branches 

 of lofty oaks, pines, sycamores, etc. In mountainous regions the nests 

 are often placed on the narrow ledges of cliffs. The eggs can not be 

 distinguished from those of B. borealis. 



339. Buteo lineatus (Gmel.) [439.] 



Red-shouldered Mainrk. 



Hab. Eastern North America, north to Nova Scotia; west to the edge of the Great Plains. 



This large species is one of the commonest hawks in the United 

 States, and it is especially abundant in winter, from which it receives 

 the name of Winter Falcon, but it is not more hardy than the Red-tail. 

 It also shares the name of Chicken Hawk, commonly applied to all the 

 larger hawks. Only occasionally it visits the barnyard, its diet is of a 

 more humble kind, such as frogs, rats, mice and small snakes. 



