Mr. R. B. Sharpe's Catalogue of Accipitres. 285 



mage assumed by the adult of the North- American form." 

 So far as I have had the opportunity of examining specimens 

 from South America, this observation is correct"^. 



Passing on to the genus Melierax, I have a few observa- 

 tions to make relative to the colour of the irides in some 

 species of that genus. 



In M. canorus Mr. Sharpe describes the colour of the iris 

 as " dark reddish brown " in the adult, and " dark brown " 

 in the immature bird. The former is in accordance with all 

 the observations that I have met with ; but as regards the 

 the colour of the eye in younger specimens, I may remark 

 that Mr. Ayres, in 'The Ibis ' for 1869 (p. 289), records the 

 iris of a young male which he obtained as being " yellow." 



In treating of the nearly allied species M. polyzonus, Mr. 

 Sharpe gives the iris of the adult male as "pale umber-brown;" 

 but Riippell, in the 'Neue Wirbelthiere ^ (p. 37), states that 

 the iris in adult birds is a " beautiful carmine-red ;" and Bar- 

 boza du Bocage, in his tenth list of the birds of Portuguese 

 West Africa, also states that it is " red." 



In the case of M. gabar, the iris of the immature bird is 

 stated by Mr. Sharpe to be yellow, which agrees with all the 

 notices which I have seen respecting it ; but as regards the 

 colour of the iris in the adult of this species, there appears to 

 be a considerable variation between the records of different 

 observers, and probably therefore in the birds themselves. 

 Mr. Sharpe quotes Andersson, who gives it as '' brilliant 

 purple"t, and Von Heuglin, according to whom it is "scarlet;" 

 Le Vaillant speaks of it as "bright yellow;" Mr. Atmore, as 

 quoted by Layard, describes it as " bright crimson ;" Mr. 

 Ayres, in 'The Ibis^ for 1869 (p. 289), mentions an adult 

 female in which it was " dark reddish yellow," Mr. Buckley, 

 in 'The Ibis^ for 1874 (p. 359), an adult male in which it 



* In the P. Z. S. for 1858, p. 150, Dr. Sclater has recorded a curious 

 variation in the form of the upper mandible in this species, as exhibited 

 in two specimens from Cliile, which are preserved in the Norwich 

 Museum. 



t I think it probable that by the term " purple " Andersson intended to 

 denote a dark red. 



