152 
Mr. J. H. Gurney^s Notes on 
nor do we see any intermediate stage between C. cinereus and 
C. thoracicus. The markings of the tail, however, do vary 
somewhat: the bars are sometimes narrower, sometimes 
broader, here and there more sharply defined, elsewhere more 
obsolete, in some parts lighter, almost pure white, in others 
shaded with smoky grey. The whole-coloured Serpent-Eagle 
occurs but rarely in North-eastern Africa; we found it in 
winter in the Quola of Western Abyssinia and, at about the 
same time of year, on the Upper White and Blue Nile; and 
we also saw a bird, certainly of this species, in the low lands 
between Semien and Wogara in Abyssinia. Antinori found 
it in December near Dokah, in East Sennaar; according to 
Buppell it occurs occasionally in Abyssinia'’’*. 
I propose now to refer to some South-African specimens 
which I have recently examined, and which appear to me to 
illustrate the changes of plumage ordinarily incident to the 
white-bellied bird, to which, for the sake of distinction, I will 
provisionally apply Sir A. Smith’s specific name oipectoralis ; 
and I will number these specimens as I proceed, for the con¬ 
venience of reference, tracing the changes from the nestling- 
plumage to that of the fully adult bird. 
(No. 1.) The youngest specimen that I have seenf is a 
male from Kuruman, in the collection of Captain Shelley, 
which exhibits on many of the rectrices the elongation of the 
shaft beyond the web which is so frequent in very young 
birds, one of which even now retains a slight downy tip, 
whilst several of the primaries are still enclosed at the base 
in the sheath indicative of a growing feather. Notwith¬ 
standing these appearances I think it probable that this bird 
had left the nest for some weeks, as the margins of the fea- 
* Riippell speaks of Circa'etus thoracicus, Cuv., —^pectoralis, Smith,” as 
“ frequent in Abyssinia,”, and of “ C. cinereus, Vieill., =/wwereMS,” as occa¬ 
sional in Abyssinia f ’ vide ‘ Systematische Uebersicht,’ p. 10. 
t A still younger specimen unfortunately escaped my recollection till 
after the above was in the printer’s hands; it is preserved in the Museum 
at Cambridge, where I examined it and made the following memorandum 
respecting it:—'“Nestling, with much down remaining; under surface 
wholly cinnamon-brown ; upper surface similar, but with blackish brown 
centres to the feathers.” 
