


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- 
eauda which were obtained from the Museum at Geneva, and 
which 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 Rupornis. I may add that a specimen of 
A. nitida is at the present time (August 1876) living in the 
Zoologica] Gardens, and in process of change from the :mma- 
ture 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 Aquilinze, 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 always 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-feathers 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. I1I.—VOL. VI. 21 

