FALCONID.E — THE FALCONS. HI 



saker, Schleg. (Gray's Hand List, No. 176), seems, to jiidge from the descvip- 

 tious and figures wliicli I have seen, to be also merely a form of the same 

 species, but I have seen no specimens of it. 



Falco (Hierofalco) gjrrfalco, Linn. 



Var. candicans, Gmeldj. 



WHITE GEEFALCON. 



Aa-ipifcr falco freti hrtdsonis, Bki.':. Orii. I, 356, 17()3. A. gijrfaico, Bp.iss. Orn. I, 370, 

 pi. XXX, f. 2, 1763. Falco rusticulus, F.iBR. Faun. Green, p. 55, 17S0. — Lath. Syu. 

 Supp. I, 15, 17S1. F. candkans, Gmel. Syst. Nat. p. 275, 1788. — Daud. Tr. Orn. 

 n, 101, 1800. — Bexick, Isis, 1824, 882. —Schleg. Krit. Ubers. p. 1, 1844.— 

 BoxAP. Eev. Zool. 1850, 484; Consp. Av. p. 33. — Ca.s.six, Proc. Ac. Nat. Sc. Phil. 

 1855, 278 ; Bird.s N. Am. 1S58, 13. — Strickl. Orn. Syn. 1, 77, 1855. — Blasius, 

 Cab. Jour. 1862, 43 (thinks all boreal ones same in Europe and Ameriea). — Elliot, 

 Birds N. Am. pi. xii. Hierofalco candkans, Cuv. Reg. An. ed. 1, L 312, 1817 ; cd. 2, I, 

 323, 1829. — Less. Man. Cm. I, 80, 1828 ; Tr. Orn. p. 97, pi. xvi, p. 2. — Quay, Hand 

 List I, 18, 1869. Falco islandkiis. Lath. Ind. Orn. p. 32, 1790; Syn. I, 71, A, B; 

 Gen. Hist. \, 72, A, 1821. — Steph. Zool. XIH, pt. ii, p. 39, 1826. — Gould, B. Eur. 

 pi. xix. — Aui). Birds Am. 1831, pi. ccclxvi. F. bicleo p, Lath. lud. Orn. p. 24, 1790 ; 

 Gen. Hist. I, 80, A. F. la<jopus, ^, L.iTH. Lid. Orn. p. 19, 1790 ; Syn. Supp. L 36 ; 

 Gen. Hist. ], 63, A. F. ijraiilandkiat, Daud. Tr. Orn. 11, 157, 1800. Hkrnfalco 

 grcenlandkus, Brehm. Voy. Dcutsch, I, 16, 1831. F. ijyrfako, Bonap. List, p. 4, 

 1838. 



Sp. Char. AduU (J, 1S,.077, Greenland; Univ. Zool. Mus. Copenhagen). Ground- 

 color entirely pure white ; whole upper surface (posterior to the nape) with transver.se 

 creseentic bars of dark plunibeous-brown, generally about two on each feather, the first 

 concealed by the feather which overlaps. Primaries crossed at regular intervals with 

 quadrate spots of the same tint, these becoming fused toward ends of quills, forming a 

 terminal dusky space of two or three inches in extent ; tips of all the quills narrowly 

 white ; the black bars do not extend quite to the primary coverts, and decrease both in 

 extent and regularity toward the base. Middle tail-feathers crossed with seven or eight 

 imperfect bars of dussky, the .shafts of the feathers blackish ; rest of tail immaculate, tlie 

 shafts pure white. Nape with a veiy few fine shaft-streaks of dusky. Whole lower sur- 

 face of body and wing utterly immaculate. Wing-ibrmula, 2-3-1. Wing, 16.50; 

 tail, 9.00; cuhnen, 1.05; tarsus, 2.10-1.35; middle toe, 2.20; inner, 1.50; outer, 1.50; 

 posterior, 1.00. 



(Ko. 56,1.52, 9 1 Greenland ; Schliiter Collection.) Head above, occiput, nape, and 

 upper half of ear-coverts, with spaise shaft-streak.s of black, these most numerous on the 

 latter region ; primaries barred to the coverts. Tail entirely cros.sed by eleven plum- 

 beous bars. Bars above clearer plumbeous. The snowy-white beneath is relieved by a 

 few minute vari.able flecks of dusky upon the lower part of the abdomen, becoming larger 

 as they approach the sides. Wing-formula, 2-3 - 1. Wing, 10.70; tail, 9.30. 



Jiiv. transition stage? ( (J, 56,047, " Hoher Norden " ; Schliiter Collection). Markings 

 above quite different from those of the two preceding; each feather has a largo central 

 longitudinal .sagittate spot of dusky, leaving only the borders (of the exposed portion) 

 white; on the primaries the dusky is almost confined to the terminal portion ; the rump 

 and upper tail-coverts have each feathers with a medial longitudinal stripe of dusky. The 

 tail is immaculate, but the shafts of the middle feathers are dusky. The neck, breast, ab- 



