8(> THE HAWKS AND OWLS OF THE UNITED STATES. 



In the vicinity of Tucson the eggs arc deposited about the middle of 

 May, though nests in which the eggs were only partially incubated 

 have been found as late as June 15. The usual complement of eggs is 

 two, though three are not uncommon. The nest is placed in the tops 

 of high trees, often 50 to 75 feet from the ground. According to Capt. 

 Charles E. Bendire, it is composed of the fresh twigs of the cottonwood, 

 with some of the leaves attached. He has observed the birds break in g 

 off the branches with their talons as they pass rapidly by the tree. In 

 some cases the lining of the nest is composed of dry leaves of the Cot- 

 tonwood, while in others the strips of bark are also used. 



This hawk frequents the more open groves and the borders of timber? 

 and usually is not shy or difficult to approach. The flight is swift and 

 falcon-like. Capt. Bendire states that its note resembles very closely 

 that of the long-billed curlew and at first he mistook it for that of the 

 latter bird. 



The Mexican Goshawk, like a number of other tropical species which 

 cross the southern border, is of very little economic importance in the 

 present connection on account of its limited distribution in our terri- 

 tory. 



DESCRIPTION. 



Above deep ash gray; top of head and back of neck with five blackish 

 shaft streaks; tail black, tipped with white, and crossed by two or 

 three narrow bands of white; feathers covering base of tail white; be- 

 low white, very regularly barred with ashy, the stripes being farther 

 apart on flanks and belly. 



Length: 10 to 18 inches (406 to 457 mm ); wing, 9.50 to 11.70 inches 

 (242 to 297 mra ); tail, 6.70 to 8.20 inches (170 to 208 mm ). 



ROUGH-LEGGED HAWK. 



Archibuteo lagopus sancti-johannis. 



[Plate 11— Adult,] 



The Bough-legged Hawk inhabits, during the different portions of 

 tlie year, the greater part of North America north of Mexico, but in 

 summer is found north of the United States only. In the West it ex- 

 tends far south in winter, occurring not uncommonly in suitable locali- 

 ties in Kansas, New Mexico, Arizona, and southern California. In the 

 east its winter range is more restricted, and the species may be con- 

 sidered rare or of casual occurrence south of the Potomac Eiver. The 

 limit of its northern range in winter depends much more upon the 

 presence or absence of snow than upon temperature. It retreats 

 and advances from one feeding ground to another as the snow comes 

 and goes, keeping just south of the snow belt. In average winters it 

 is found through southern New England, southern New York. Illinois, 



