Mr. R. B. Sharpe’s Catalogue of Accipitres. 315 
white under surface is a normal phase of the nestling plu- 
mage, appertaining to an earlier age than that of either of 
the two specimens described under the head of “ young” by 
Mr. Sharpe. 
The second complete stage of dress is that which Mr. 
Sharpe terms “ mature,” but which, as it seems to me, by no 
means merits that title. This phase of plumage is figured 
by Temminck in the Planches Coloriées, t. 115*; the third 
stage of plumage is figured in the same work on t. 104, and 
the fourth on t: 108. The oldest specimen described in Mr. 
Sharpe’s volume has not yet fully acquired this fourth and 
final costume, of which the examples preserved in the mu- 
seums in this country are by no means numerous. I only 
recollect two such, viz. one in the British Museum from 
Panama, which I believe has been acquired since the publi- 
cation of Mr. Sharpe’s volume, and one in the Norwich 
Museum from Brazil. 
The passage from one stage of plumage to another is at- 
tained, as Mr. Sharpe has well pointed out, by approaches 
which are often irregular in their progress, and which vary 
much in different individuals. 
Taking the second description of the young plumage given 
by Mr. Sharpe at p. 831 of his volume, paragraph 2 (but with 
the under surface entirely white, as indicated by Léotaud), as 
the first or nestling stage of plumage, I may mention that 
the passage from this to the second stage appears to com- 
mence with the following changes, viz.:—AIl the dark parts of 
the upper surface become of a blacker brown, and the rufous 
edgings to the feathers of the mantle gradually disappear ; the 
dark transverse bands on the tail, which are four in number 
in the majority of very young birds, but occasionally five, 
are reduced to three, and become broader and blacker, whilst 
the interspaces between them change from light brown to 
slaty grey, which is frequently mingled with white on the 
upper edge of the middle interspace, and more largely so in 
the upper one; the base of the rectrices also becomes white 
* This plate is accidentally referred to erroneously in Mr. Sharpe’s 
volume as pl. 105. 
