Mr. R. B. Sharpe's Catalogue of Accipitrcs. 455 



shortly after it was acquired by the Museum, that it had been 

 obtained on the river Syr Daria, in Khokan. 



The genus Polioaetus is associated by Mr. Sharpe with that 

 of Pandion in a separate suborder, to which he assigns the 

 title of Pandiones. I agree with him that it is right that 

 Pandion should be thus separated from the Sea-Eagles, as it 

 certainly is a very peculiar and isolated form ; but I cannot 

 assent to the propriety of removing the genus Polioaetus from 

 among the Sea-Eagles to place it with the Ospreys. 



The leading character which Mr. Sharpe attributes to his 

 suborder "^ Pandiones"* is that of the "outer toe'^ being 

 " reversible ; " but although this is the fact in Pandion, I am 

 not aware that it is so in Polioaetus, or that it has been so 

 recorded by any observer who has handled in the flesh birds 

 of that genus ; and, indeed, Jerdon seems to imply the con- 

 trary, since he speaks of Polioaetus as having " differently 

 formed feet " from Pandion {vide ^ Birds of India,' vol. i. p. 81) . 



The only peculiarities in which, as it appears to me, Po- 

 lioaetus is assimilated to Pandion rather than to Haliaetus 

 are the shortness of the tibial feathers, which, however, are 

 slightly longer than in Pandion, and the circumstance of the 

 under surface of the claws being destitute of a grooved channel. 

 On the other hand, two very remarkable characteristics of 

 Pandion, the absence of an after-shaft from the contour- 

 feathers, and the equal size of the claws, do not exist in Po- 

 lioaetus, in which genus, moreover, the scntellation of the 

 tarsi and toes resembles that of Haliaetus, and is altogether 

 different from the roughened reticulation which characterizes 

 those parts in Pandion. 



The genus Polioaetus comprises three species, P. ichthyaetus, 

 P. plumbeus, and P. hmnilis. Of these Mr. Sharpe only 

 recognizes, in his volume, as good species the first and the 

 last ; but I think that the distinctness of P. plumbeus must 

 be admitted, specifically from P. ichtJiyaetus, and sub-speci- 

 fically from P. humilis. 



* Mr. Sharpe places his suborder "Pandiones" at the close of his 

 volume, and I propose to adopt a similar order of sequence as relates to 

 the genus Pandion. 



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