478 Field Museum of Natural History — Zoology, Vol. IX. 



the Academy of Natural Sciences in that city; while it has been 

 observed on two occasions by the writer, once near Mount Carmel 

 and once in Lawrence County (near the town of Bridgeport), both 

 during the month of September, 187 1." 



There is no satisfactory record for Wisconsin. According to 

 Kumlien and Hollister (Birds of Wisconsin, 1903, p. 132) a bird came 

 into the possession of Thure Kumlien in a badly decomposed state 

 sometime in the early sixties, " which was never satisfactorily identi- 

 fied otherwise than as a young prairie falcon." 



Subgenus RHVNCHODON Nitzsch. 

 169. Falco peregrinus anatum (Bonap.). 

 Duck Hawk. Peregrine Falcon. 



Distr. : North America, breeding in many parts of the United 

 States; south in winter as far as Chile, South America. 



Adult. Crown, blackish, rest of upper plumage, slaty plumbeous, 

 or dark bluish ash color, the edges of the feathers, paler; under parts, 

 varying from white to buff, barred and spotted with blackish, except 

 on the throat and breast, which are usually free from markings ; sides 

 of face below the eye, black; primaries, blackish, barred on inner webs 

 with buffy white; upper surface of tail, faintly barred with gray, the 

 tips, whitish; under surface of tail feathers, grayish brown; barred 

 with whitish; most of bill, black, the cere and base of bill, yellow; 

 feet, dull yellow. 



Immature : Crown, tawny, streaked with dark brown, rest of upper 

 parts, dark slate color, mixed with rusty brown and rufous; under 

 parts, tawny or ochraceous buff, streaked (not barred) and marked 

 with dark brown, except on the throat which is usually immaculate 

 or at most marked with a few hair-like lines; a black streak below 

 the eye, extending down sides of throat; inner webs of primaries, 

 barred with buff; tail, grayish brown, with irregular bars of pale 

 rufous, the tips, white. 



Male: Length, 16.50; wing, 12 to 13; tail, 6.50; tarsus, 1.70. 



Female: Length, 18.50; wing, 13 to 14.75; tail, 7 to 8; tarsus, 

 1.80. 



Although by no means common, the Duck Hawk occurs in Illinois 

 and Wisconsin during the migrations in spring and fall and a few re- 

 main during the summer. Prof. Ridgway found several pairs nesting 

 in the neighborhood of Mt. Carmel, 111. (Orn. of Illinois, p. 1889, p. 433). 

 Kumlien and Hollister state that it formerly bred at Racine, Wis- 

 consin. 



