Mr. R. B. Sharpe's Catalogue of Accipitres. 483 



red/' the latter tint being probably indicative of more ad- 

 vanced age than the former. 



The Norwich Museum possesses two examples of R. griseo- 

 cauda which were obtained from the Museum at Geneva, and 

 wdiich were said to have been collected by De Saussure in 

 Cuba ; the species, however, is not included by Gundlach 

 in his work on the birds of that island. 



The third and remaining group (that to which I would re- 

 strict the generic, or, rather, subgeneric name of Asturina) 

 consists of two nearly allied species, A. nitida and A. plagi- 

 ata, the former being the more southern, and the latter the 

 more northern form ; both of these exhibit a remarkable dif- 

 ference in marking and in coloration between the immature 

 and adult plumages, the contrast between the two stages being 

 much more striking than in the corresponding ages of the 

 various species of Rvpornis. I may add that a specimen of 

 A. nitida is at the present time (August 1876) living in the 

 Zoological Gardens, and in process of change from the imma- 

 tm'e to the adult dress ; in this example the iris is hazel and 

 the cere yellow. 



There are two Old- World genera, Butastur and Asturinula, 

 which appear to me to be essentially and somewhat closely 

 allied to Rupornis and to Asturina respectively, but which 

 Mr. Sharpe includes among the Aquilinae, apparently on 

 account of the hinder aspect of the tarsus being reticulate 

 rather than scutellate — a mode of diagnosis which is, no doubt, 

 technically convenient, but which does not alw^ays square (as 

 I venture to think) with the general natural characters of the 

 birds to which it is applied, and which I therefore, in the case 

 of these and some other genera, feel compelled to disregard. 



Between Rupornis and Butastur there is one very remark- 

 able coincidence of colouring, in the circumstance that in the 

 adult birds of all the species of both genera the webs of the 

 quill-feat tiers of the wing are more or less conspicuously 

 tinged with rufous ; and I cannot but think that this circum- 

 stance, combined with a considerable similarity in the general 

 build and aspect of the birds of these two genera, points them 



SER. III. VOL. VI. 2 L 



