242 BLUE HAWK, OR HEN-HARRIER. 



the other. The F. cineraeeus has two white spots near the eyes, which 

 are not in the F. cyanetis. The young of the former is beneath rusty 

 without spots. Thus slight, but constant differences, are seen to repre- 

 sent a species, while the most striking discrepancies in color, size, and 

 (not in this, but in other instances) even of form, prove mere variations 

 of sex or age ! We cannot wonder at the two real species having always 

 been confounded amidst the chaotic indications of the present. 



Even Wilson was not free from the error which had prevailed for so 

 long a period in scientific Europe, that the Ring-tail and Hen-Harrier 

 were two species. Though he did not publish a figure of the present in 

 the adult plumage of the male, he was well acquainted with it as an 

 inhabitant of the Southern States ; for there can be no doubt that it is 

 the much-desired Blue Hawk which he was so anxious to procure ; the 

 only land bird he intended to add to his Ornithology, or at least the 

 only one he left registered in his posthumous list. It was chiefly because 

 he was not aware of this fact, and thought that no Blue Hawk existed 

 in America corresponding to the European Hen-Harrier, that Mr. 

 Sabine, in the Appendix to Franklin's Expedition above quoted, per- 

 sisted in declaring that the Marsh-Hawk was a distinct species peculiar 

 to America, of which he supposed the Hudson's Bay Ring-tail to be the 

 young. The differences which he detected on comparing it with the 

 European Ring-tail, must have been owing to the different state of 

 plumage of his specimen of this ultra-changeable species. If, however, 

 he had not mentioned the colors merely, as bringing it nearer to the 

 Ash-colored Falcon of Montague, we might be inclined to believe that 

 lb' specimen he examined was indeed a young bird of that species, 

 which, though as yet unobserved, may after all possibly be found in 

 North America. At all events, Wilson's and the numerous American 

 specimens that have passed under our examination, were all young Hen- 

 Harriers. 



After having stated that the error of considering the Hen-Harrier 

 and Ring-tail as different species had prevailed for years in Europe, it 

 is but just to mention, that Aldrovandi, Brisson, Ray, and others of the 

 older authors, were perfectly in accordance with nature on this point. 

 It was perhaps with Linn^, or at least with Buffon, Gmelin, Pennant, 

 and Latham himself, who afterwards corrected it, that the error 

 originated. Latham, confident of his own observations and those of 

 Pennant, who had found males of the species said to be the female of 

 the Falco cyaneus (Hen-Harrier), and not reflecting that these males 

 might be the young, exclaims, "authors have never blundered more 

 than in making this bird (the Ring-tail) the same species with the last 

 mentioned (Hen-Harrier) ;" an opinion that he was afterwards obliged 

 to recant. In physical science we cannot be too cautious in rejecting 

 facts, nor too careful in distinguishing in an author's statement, what 



