Ml'. R. B. Sharpe's Catalogue of Accipitres. 583 



is usual in adult Grey Falcons from Greenland ; the imma- 

 ture bird exactly resembled a young Icelandic specimen. 



Professor Newton exhibited these specimens at a meeting 

 of the Zoological Society, on June 9, 1870 ; and the following 

 note respecting them occurs in the records of that meeting'^, 

 " The birds from Alaska Professor Newton referred without 

 doubt to F. islandicus, though belonging to the darker phase 

 of that form." 



In a postscript, dated 6 May 1871, to a letter written by 

 Professor Newton and published in the ' Proceedings of the 

 Academy of Natural Sciences of Philadelphia ' for 1871, 

 p. 95, the Professor alludes to such of these specimens as 

 were adult in the following words : — " These are adult, and 

 differ from Icelandic examples only in being slightly darker." 



In the autumn of 1872, the female Falcon marked No. 

 43144^ was again sent to this country, for examination by 

 Mr. Dresser, and with it three other specimens of the same 

 North- American race, respectively labelled No. 51690, No. 

 35451, and No. 43142. Of these the first two were males, 

 adult, but one apparently older than the other, from Yukon, 

 and the last a female, not quite adult, the exact locality of 

 which was not specified. 



After inspecting these specimens, for the opportunity of 

 doing which I was indebted to the kind attention of Mr. 

 Dresser, I made a memorandum to the effect that they seemed 

 to me not to be separable from Icelandic examples, and more 

 particularly one specimen, respecting which I made the 

 following note: — "No. 35451, which seems the only very 

 adult bird, agrees very well with a very adult male from 

 Iceland •\, which lived ten years in the Zoological Gardens, 

 and is figured in Wolf's ' Zoological Sketches.' " 



Mr. Dresser, on the contrary, arrived at the conclusion that 

 the last-named four Falcons were all referable to H.gyrfalco ; 

 and it may be convenient that I should cite the following 



* Vide P. Z. S. 1870, p. 384. 



t This specimen is preserved in the Norwich Museum ; it is noticeable 

 that the comparison was made with a true Icelandic Falcon, and not with 

 the Grej' Falcon of Greenland, H. holhcdli. 



2r 2 



