1873.] MR. R. B. SHARPE ON FALCO ARCTICUS. 415 



fore, can hope to say positively what Holboll' a Falco arcticus really 

 was ; but there is little doubt that the occurrence of a form of 

 Iceland Falcon in Greenland led him to see two species, though 

 it bears some resemblance to the true F. candicans when it is very 

 old. Should ornithologists agree with me, that the bird hitherto 

 known as Falco islandus, from Greenland, is really the origin of 

 Holboll's F. arcticus, I propose to call it after that unfortunate gentle- 

 man, as his title has already been preoccupied by Gmelin, who con- 

 ferred it on the Falcon d'Islande of Brisson (Orn. i. p. 336). This 

 bird, said to be from Iceland, has never been satisfactorily identified, 

 but is described as being like the Peregrine, with a yellow eye. 



I am by no means the first to recognize the distinctness of this 

 fourth Jer Falcon; for Messrs. Salvin and Brodrick have already drawn 

 attention to it, calling it the "light variety" of the Iceland Falcon ; 

 while Professor Schlegel has, most justly in my opinion, considered 

 it as distinct from the true Iceland Jer Falcon as is the Jer Falcon of 

 Norway {Falco gyrfalco). The following will, I believe, be found to 

 be the correct synonymy of the species : — 



Falco holbcslli, sp. n. 



Falco arcticus (nee Gm.), Holboll, Zeitschr. f. d. ges. Naturw. iii. 

 p. 426 (1854); Blasius, Naumannia (1857), p. 238; id. Nactr. 

 Naum. Vog. Deutschl. p. 19 (1860, nee Taf. 390. fig. 2)*. 



Iceland Falcon (light variety), Salvin & Brodr. Falconry, p. 87,pl.x. 

 (1855). 



Falco gyrfalco grcenlandicus, Schl. Mus. P.-B. Falc. p. 13 (1862). 



Adult male. Head white, with blackish shaft-stripes, a little 

 broader on the nape ; rest of the upper surface greyish brown, with 

 more or less of a bluish shade according to the light, transversely 

 banded and tipped with white ; quills brown, edged and tipped with 

 white, and freckled on the outer webs ; on the smaller secondaries 

 are indistinct bands of brown, alternating with bars of greyish white, 

 the latter plentifully freckled with brown ; tail ashy grey, tipped 

 with white, freckled plentifully with brown, and showing cross bars 

 on the outer feathers ; under surface white, the throat and chest 

 entirely unspotted, the rest of the body sparingly spotted with 

 blackish, taking the form of bars on the flanks, thighs, and under 

 tail-coverts ; under wing-coverts white, spotted with black ; inner face 

 of wing whitish, barred with blackish ; cere, orbits, and feet yellow ; 

 bill bluish, yellow at base of lower mandible ; iris dark. Total length 



19 inches, culmen T3, wing 14, tail 7*5, tarsus 2*1. 



Adult female. Similar to the male, but larger. Total length 



20 inches, culmen 1*4, wing 15-2, tail 5 - 5, tarsus 2*2. 

 Hab. Greenland. 



Falco holbcelli is distinguished from F. islandus by its smaller 

 size, by the larger white spots and bars on the upper surface, which 



* As Professor Blasius, in quoting Holboll as the describer of this species 

 designates the bird he wishes to be recognized as F. arcticus, I have referred his 

 notices to this Falcon ; but he evidently mixes up F. candicans, F. islandus, and 

 F. holhix'U together : witness his references to the plates in ' Naumannia.' 



