Mr. R. B. Sharpe's Catalogue of Accipitres. 95 



served by Taylor, a row of black spots on the white portion 

 of the w^ing-feathers." 



Passing on from the Vulturidse to the Polyborinse, I may 

 mention that the Norwich Museum possesses an adult speci- 

 men of Polyborus cheriway from Brazil, a habitat not quoted 

 for this more northern race by Mr. Sharpe ; but unfortunately 

 we have no record of the district in Brazil where this speci- 

 men was obtained. 



Referring to the succeeding genus Ibycter, I am able to 

 supplement Mr. Sharpens description of the adult plumage of 

 Ibycter ater by some particulars respecting an immature spe- 

 cimen in the Norwich Museum from the river Amazon. In 

 this example the white caudal band extends over the upper 

 two thirds of the tail, and is crossed by five successive trans- 

 verse black bars, increasing in breadth from the top down- 

 wards, the uppermost bar being about a quarter of an inch in 

 depth, and the lowest nearly half an inch, causing the general 

 appearance of the tail to bear a marked resemblance to the 

 tail of the adult bird of Ibycter chimachima. 



The remainder of the plumage of this specimen is of a 

 paler and more purplish black than in the adult bird, except 

 some portions of the plumage of the back and breast, which 

 seem to have been recently moulted, and to have thus assumed 

 the ordinary adult coloration. 



A specimen resembling the above in the markings of the 

 tail is figured in Temminck^s ' Planches Coloriees ' (pi. 342) . 



It seems probable that Ibycter fasciatus of Spix is merely 

 the immature bird of /. ater in the plumage above described. 



In a very nearly adult specimen from Quito, in the Nor- 

 wich Museum, the pure white caudal band is varied by two 

 small isolated black spots, which I have no doubt are the re- 

 mains of the black transverse bars which cross this portion 

 of the tail in the young bird. A similar stage of plumage, 

 but with more numerous black spots, is figured in the 

 ' Planches Coloriees ' (pi. 37). 



It appears to me that the late Mr. Gr. R. Gray in his 'Genera 

 of Birds,' and in his ' Hand-list,' followed a natural arrange- 

 ment in restricting the genus Ibycter to the arboreal species 



