291 



ARCHWUTEO LAGOPUS. 



ARCHIBUTEO LAGOPUS. 

 Rough-legged Hawk. 

 Archibulco laynpus Gray, List Genera of Birds; IS.'j.'), 3. 



DESCRIPTION. 



Sp. Cn. Form, vei-y rolnist. Size l;irge. Sternum, stout, rather wide, with the marginal indentations quite small. 

 Timirue, quite fleshy, widening toward tip which is rounded but not bifid. Sterno-trachealis, weak. Tlie glands of the 

 proventriculus are arranged in five longitudinal, pj'ramid-shaped ridges. Coeca, very small. Sexes, similar in color. 



Light stage. 



Color. Ad^ilt. Above, everywhere uniform dark-brown, with the feathers more or less edged with wliitish and ru- 

 fous. Outer edges of primaries, ashy, while the inner webs and under surface are white, and the entire wing is obscurely 

 barred with duskj'. Tlie tail is tipped with j'ellowish-white, and the base and nearly all the lower portion are wliite, the 

 wholi; b^iing banded with dark-brown. Sides and base of upper tail coverts, also white, and the remaining portions are 

 banded with it. Side* of head, yellowish-white, streaked with sooty-brown. Beneath, everywhere pale yellnwish-white, 

 briiad'.y s:reaked in a band on the breast with dark-brown. There is a broad continuous band of dark-brown cri;ssing the 

 middli! of the liody , and the undtr wing coverts are streaked with dusky and the ti]is are black. The tibia i'^ finely barred 

 with wavy linos of rufous and dark-brown. The throat is also streaked with dark-brown. 



Yiiuny. Quite similar to the adult but macli more decidedly rufous above and below. The top of the head is very 

 light, only being narrowly streaked with brown. 



Dark stage. 



Color. Adull. Uniform so:)ty-l)lack everyivhere, excepting under portions of wings, base of tail, and irregular mark- 

 ings on it, all of which are white. 



Yvunij. A'ery dark, like the above described, but more or less streaked, spotted, and mottled on both surfaces with 

 brown and rufous. Bill, black, orange at base of lower mandible, cere and feet, orange, iris, brown, in all stages. 



OBSERVATIONS. 



It is extremsly difficult to givean ideaof the variable plumage of this species. Ihave described the extremes, but there 

 are all gradations between and in some specimens the three colors, lilack, wliitc, and rufous, are almost indescribably 

 mise 1 and in others, appear in patches. Sometimes the tibia is unspotted, lieing either yellowish-rufous or decidedly red- 

 dish. The light stage i< the typical layopus of authors and previous to 1873 the dark stage was considered a species, and 

 called '■■Sancli Johannis". In spite of this variation in plumage, no one in our section will fail to recognize this fine bird 

 by the w lo'Iy foatheied tnr.sus, size, and colors as described. Distributed asa summer resident throughout North America, 

 north of latitude 45'; wintering in New England and southward, at least into Pennsylvania. 



DIMENSIONS. 



Average inea.surementsoffo'inabsp3oimens from Eastern North America. Length, 2'3'30, stretch, 53- 15: wing, IG'55; 

 tail, 9 a.*); liill, •O.'i; tai-sus, 2-75. Longest specimen, 23-25; greatest extent of wing, 53-80; longest wing, 17-25; tail, 9 7f ; 

 bill, l-dO; tarsus, 3 00. Shortest specimen, 21-45: smallest extent of wing, 5200; 'shortest wing, 1600; tail, 9 00; bill, 90; 

 tarsus, 2-50. 



Average moasureaicnts of male specimens from Eastern North America. Length, 2(i-35; .stretch, 5200; wing, 16-15; 

 tail, 8 45; bill, -95; tai-sus, 265. Longest .specimen, 2.115; greatest extent of wing, 52-25; longest wing, 16 25; tail, 8-5i); 

 bill, 1-00; tarsus, 2-75. Shortest specimen, 19-.50; smallest extent of wing, 51-75, shortest wing, 15-85; tail, 8-35; bill, -85, 

 tarsus, 2-40. 



DESCRIPTION OF NESTS AND EGGS. 



tresis, placed in trees or on rocky olilis; they are very bulky structures, composed of sticks and twigs, arranged in a 

 compact manner, lined with leaves etc. 



Eijys, four t.) six in numl)er, varying from spherical to oval in form, ashy or yellowish-white in color, spotted and blotclicd 

 irregularly and rather faintly with redtlish-brown and umlier, with frequent markings of purplish. Dimensions from 

 1 75x2-12 to 1-82x2 26. 



HABITS. 



When the briglitcr imd warmer day.s of early November have past and the icy winds, 

 blowing from the northward, constantly remind us, with ever increasing force, that the 



