BROWN AND WHITE JER-FALCONS. 17 
FALCO CANDICANS. 
WuitE Jer-F acon. 
Accipiter falco freti hudsonis, Briss. Orn. i. p. 356 (1760). 
Accipiter gyrfalco, Briss. Orn. i. pl. xxx. fig. 2 (1760). 
Falco rusticolus, Faber, Faun. Groenl. p. 55 (1780). 
Falco islandus, Fuber, Faun. Groenl. p. 58 (1780) ; Lath, Gen. Syn. Suppl. i. p. 282 
(1787). 
Falco islandus 3. albus, Gel. Syst. Nat. i. p. 271 (1788, ex Brinn.). 
Falco candicans, Gmel. Syst. Nat. i. p. 275 (1788); et auctorum plurimorum— 
Schlegel, Strickland, Reinhardt, Newton, Gray, Sharpe, &c. 
Falco islandicus (Briss.), apud Lath. Ind. Orn. i. p. 32 (1799). 
Falco groenlandicus, Turton’s Gen. Syst. Nat. i. p. 147 (1806). 
Hierofalco candicans (Gmel.), Cuv. Réegne An. i. p. 312 (1817). 
Falco gyrfaleo, Linn. apud Pall. Zoogr. Rosso-As. i. p. 824 (1826). 
Falco islandicus candicans, Holb. Zeitschr. Ges. Nat. iii. p. 426 (1854). 
Falco (Hierofalco) gyrfalco (Linn.), var. candicans (Gimel.), Ridgw. N. Amer. Birds, 
iii. p. 111 (1874). 
An anonymous reviewer, in an able article on this subject (Ibis, 1862, 
p- 44) recognizes three species of Jer-Falcons, F. gyrfalco, F. candicans, 
and F. islandus. Nine years later Newton (Yarr. Brit. B. i. pp. 36-52) 
does not suggest any alteration in this conclusion. Sharpe (Cat. Birds 
Brit. Mus. i. p. 410), in 1874, admits the validity of the two first-men- 
tioned species, but splits the last-mentioned into two, F. islandus and F. 
holbelli. In the same year Baird, Brewer, and Ridgway (Hist. N. Amer. 
Birds, iii. p. 108) only recognize one species, which they subdivide into 
five varieties. F. gyrfalco is split into var. sacer, var. gyrfalco, and var. 
labradora; F. candicans is called var. candicans; and F. islandus and F. 
holbeili ave united under the name of var. islandicus. In 1876 Dresser 
(‘Birds of Europe,’ vi. pp. 15-80) reunites var. sacer and var. gyrfalco 
under the name of F. gyrfalco, but admits the distinctness of F. labradorus. 
F. candicans is recognized as a good species, but F. holbelli is reunited 
with F. islandus under the latter name. 
The characters upon which these alleged species are based are very 
variable, and the localities of examples in various museums are very inexact. 
In the literature of the subject still more uncertainty prevails, in conse- 
quence of wrong determination of immature birds; but after making 
allowance for these supposed errors, the following appears to me to be the 
most rational solution of this puzzling problem. 
We may at once dismiss F. labradorus as a perfectly distinct species, of 
a nearly uniform brown colour in the adult, with a few buff streaks on 
the flanks, and a perfectly brown tail. This species breeds in Eastern 
Labrador ; and there seems to be no evidence of any kind that any inter- 
mediate forms occur between it and F. gyrfalco. 
F. candicuns is the arctic form, breeding only north of the aretic circle, 
in North Greenland, and Eastern America north of Hudson’s Bay. No 
Jer-Falcon has ever been found breeding in North Russia or Siberia. The 
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