48 



wfcatxona on $alo> Pcnbcrsoni, fume. 



By W. E. Brooks. 



When Mr. Hume first shewed me the type of Falco Hender- 

 soni, I observed that it was a good and most remarkable 

 species. I had seen a good number of Punjab Sakers, as 

 well as European examples, but this splendid Yarkand Falcon 

 had a general aspect quite dissimilar to that of any Saker of 

 the well-known species. To this conviction I have adhered, 

 although I have been frequently assured that the bird was 

 only a stage of F. sacer. 



Falco Hendersoni has been opposed by Mr Gurney and by 

 Mr. Sharpe. Mr Sharpens remarks on it are to be found at 

 page 419 of his Catalogue of the Accipitres. One remark I 

 must here quote : — " In this state of plumage the bird (F. 

 sacer) is F. milvipes of Hodgson, and F. Hendersoni of 

 Hume/' I have examined Hodgson's original drawing of F. 

 milvipes, and found it to be the common sacer, as far removed 

 as could be expected from the affined F. Hendersoni. 



I think the question of identity of species is set at rest by 

 the observations of Lieutenant-Colonel N. Prjevalsky, to be 

 found in his paper, entitled. " The Birds of Mongolia, the Tan- 

 gut country, and the solitudes of Northern Tibet, published 

 in Ornithological Miscellany for January 1877, pp. 149-150." 

 I shall quote the article at the close of this paper. 



Mr. Sharpe says, the fully adult or aged Saker is very rare, 

 indeed. This being the case, how was it that all the birds 

 met with by Colonel Prjevalsky, were in the Hendersoni plu- 

 mage? Had the two species sacer and Hendersoni been 

 identical, there ought to have been one or two birds seen in 

 sacer plumage, to say the least. But, unfortunately for the 

 theory of identity, there were not. This fact alone, proves the 

 validity of Hume's species, far beyond the reach of any Dar- 

 winian argument that can be brought to bear upon it ; and 

 it also shews how worthless mere theories are in connection 

 with natural history. We are all more or less fond of theory, 

 and great strides can it would seem be taken, at all events 

 in ornithology, with the barest possible assistance of facts. Mr. 

 Darwin has proved that we are all descended from monkeys ; 

 the conclusion is received, and delights the most eminent 

 naturalists, but the specific value of that odd anomaly man has 

 not yet, I believe, been denied ; no doubt, the descent of Hender- 

 soni from sacer (or vice versa), can be equally satisfactorily 

 demonstrated, but this will scarcely affect for practical purposes 

 the specific distinctness of the two forms. 



