BIRDS OF NORTH AND MIDDLE AMERICA 665 



Falco Peregrinus nigriceps Kleinschmidt, Berajah, 1927, 113 (California; descr., 



etc.). 

 Falco peregrinus subsp. Stager, Condor, xliii, 1941, 137, in text (Texas; eating 



bats) . 



FALCO PEREGRINUS HARTERTI Buturlin " 



Siberian Peregrine Falcon 



Adults.— Simiisir to F. p. anatum but with the dark miistachial 

 stripe much narrower, leaving a conspicuous white stripe between it 

 and the dark dorsal surface of the neck, this white stripe reaching 

 quite close to the eye (about 20 mm. from it).*^ 



Juvenal.— Very similar to that of the North American race F. p. 

 anatum, but on the average with more white on the cheeks, leaving 

 the mustachial stripe narrow as in the adults; the feathers of the 

 upperparts with rust brown edgings. 



Natal down. — Not Imown. 



Adult male.—Wmg 293-315 (306.5); tail 135-144 (139.5); culmen 

 from cere 18.8-19.5 (19.2); tarsus 49.6-52.1 (50.7); middle toe with- 

 out claw 45.9-48.8 (47.3 mm.).*^ 



Adult jemale.—Wmg 344-371 (353.7); taU 167-176 (173); culmen 

 from cere 23.2-24.3 (23.8) ; tarsus 51.8-55.7 (54.1) ; middle toe without 

 claw 53.9-54.2 (54mm.).*5 



Range. — Breeds in Jakutsk and northeastern Siberia from the Lena 

 Kiver to the Kolyma and (?) to the Chuckchee Peninsula. Winters 

 southward across Asia to the southeastern part of the continent (bhds 

 seen from Siam that agree very closely with the single Alaskan record) 



« Stresemann (Ibis, 1949, 253, 255) has produced evidence that the name 

 of this race may have to be changed to Falco peregrinus japonensis Gmeiin, based 

 on Falco japonensis GmeUn, Syst. Nat., i, pt. 1, 1788, 257 (in insulis Japan— off 

 the coast of Japan). 



" This race seems to be quite variable, judging by literature. Stegmann 

 (Journ. fur Orn., Ixxxii, 1934, 228-230) describes the adult as being darker above 

 than in the nominate form (or anatum), but states that in the northern part of its 

 range harterti tends to be much lighter in coloration. Inasmuch as this subspecies 

 is included in the North American avifauna on the basis of a single record, it does 

 not seem necessary to go into great detail (nor is adequate material available on 

 which to base a thorough study). Anyone interested in studying the Asiatic 

 forms of the duck hawk may well begin with Stegmann's paper referred to above, 

 as well as Steinbacher's Erganzungsband to Hartert's Vog. pal. Fauna, Heft 5, 

 1936, pp. 396-399. 



In a general way it may be said that F. p. harterti is a fairly dark form, becoming 

 pale in the northern parts of its range, where it varies toward F. p. caeruleiceps 

 Stegmann, and darker in the southeastern part of its range, where it approaches 

 F. p. rudolfi Kleinschmidt. 



The single North American record is one of the pale northern examples (which 

 being atypical do not agree closely with a general diagnosis of the race to which 

 they belong) . 



« Four male specimens from India and Sumatra. Three female specimens 

 from India and Sumatra. 



