M7\ R, B. Sharpens Catalogue of Accipitres. 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 j 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 scutellation 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. plmnbeus, and P. humilis. Of these Mr. Sharpe only 
recognizes, in his volume, as good species the first and the 
last j but I think that the distinctness of P. plumheus must 
be admitted, specifically from P. ichthyaetus^ 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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