FALCONID^ — DIURNAL EAPTORES. 431 



11.80; tail, 7.50; culmen, .75; tarsus, 2.15 ; middle toe, 1.65. Cere, 

 base of both mandibles, eyebrow, bare orbital region, tarsi and toes, 

 clear yellow. 



Adult (?) females. A female obtained by Captain Bendire at 

 Camp Harney, Oregon, measured, when fresh, 18.50 inches in 

 length; wing, 13.25; tail, 8.00; weight 4 lbs. 12 oz. "Base of bill 

 and cere sky-blue ; tarsi and toes light greenish yellow." 



Yoimg males. A young male obtained by me November 29, 1867, 

 at Carson City, Nevada, measured as follows before being skimied : 

 Total length, 17 inches; extent, 87.75; wing, 12.25; tail, 7.50; weight 

 only 1^- lbs. Bill, very fine bluish white, shading terminally into 

 bluish slate, the point black; cere, rictus, and bare orbital region, 

 greenish white ; iris, vivid vandyke-brown ; tarsi and toes pale yel- 

 lowish, with a tinge of verdigris-green. 



This fine falcon is a mere straggler to Illinois, having been ob- 

 served on but few occasions. A specimen was obtained at Kock 

 Island, by Mr. I. D. Sargent, of Pliiladelphia, and by him pre- 

 sented to 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 Bridge- 

 port), both during the month of September, 1871. 



Subgenus Rhynchodon Nitzsch. 



Rhjjnchodon Nitzsch, Pterylog. 1840, 7, 8. Type, Falco peregriniis Lath. 



The essential characters of this subgenus having been given on 

 page 4"z8, there is no necessity for their repetition here. There is 

 but one species in North America, the circumpolar F. pcregrinvs, or 

 Peregrine Falcon. 



Falco peregrinus anatum (Bonap.) 



DUCK HAWK. 

 Popular synonyms. American Peregrine; Great-footed Falcon; Black-capped Falcon. 

 Falco peregrinus WiLS. Am. Orn. ix, 1814, 120, pi. 76.— Nutt. Man. i, 1832, 53.— AuD. Orn. 



Biog. i, 1832, 85; v, 1839, 365,pl. 16; Synop. 1839. 16; B. Am. i, I&IO, 84, pi. 20. 

 Falco navius Gmel. S. N. i, pt. i; 1788, 271. 



Falco peregrinus ticecins Eidgw. Nom. N. Am. B. 1881, No. 414. 

 Falco anatum Bonap. Comp. List, 1838. 4.— Cass, in Baird's B. N. Am. 1858. 7.— Baikd, 

 Cat. N. Am. B. 1859, No. 5. 

 Falco communis var. anatum Ridgw. in B. B. & E. Hist. N. Am. B. Hi, 1874, 128, 132. 

 Falco communis c. anatum CouES, B, N. W. 1874, 341. 



