ANNALS OF NATURAL HISTORY. 



XXVII. — Remarks on the Greenland and Iceland Falcons, 

 showing that they are distinct Species, By John Han- 

 cock*. 



[With a Plate f.] 



J HE Grey or Iceland Falcon (Falco Islandicus, Lath.) 

 and the White Gyr [Falco Gyrfalco, Linn.) are at present 

 considered^ I believe, by most English authors as one species. 

 Continental writers however disagree much on the subject ; 

 some assert that they are perfectly distinct; whilst others 

 contend that they are the same species, varying only in con- 

 sequence of age, sex, or climate. It seems strange that any 

 difference of opinion should exist respecting species so cha- 

 racteristically marked as are those two birds. Our English na- 

 turalists, it is true, have had few specimens to examine, or at 

 all events our public collections contain very few individuals ; 

 and judging from the scarcity of the species, it is not likely 

 that many specimens have found their way into private cabi- 

 nets. This is not the case with continental writers ; they have 

 been more fortunate in having numerous specimens before 

 them, but by assuming that these birds go on changing their 

 plumages year after year for a long period, they have been 

 led into much confusion, and have not yet arrived at any sa- 

 tisfactory conclusion. This being the state of the question, 

 and having recently had many opportunities of examining in- 

 dividuals of both the Iceland and the Greenland birds, I wish 

 to lay before this meeting the result of such examination, 

 more particularly as I feel a strong conviction that these birds 

 are perfectly distinct. That my reasons for so considering them 

 may be as clearly understood as possible, I shall, in the first 

 place, detail what led me to this conviction. I shall then 

 make some remarks by way of elucidation, and afterwards de- 



* Read in the Natural History Section of the Meeting of the British 

 Association, Newcastle, and communicated by the author. 



t This plate will be given in the Supplement to the present volume. — 

 Edit. 



Ann.Nat.Hist.Yol.2. No. 10. Dec. 1838. r 



