Our Birds of Prey. 157 
a darker tint, and according to age, showing the white 
and black stages to the adult. 
This large hawk is one of the commonest in the 
colony, being distributed all over the coast area. I have 
never met with it in the interior, nor in the forest or 
hilly districts; but along the estuarine parts of the great 
rivers, and the tidal portions of the main creeks, it is to 
be met with everywhere, especially about the culti- 
vated districts near the town, and even in the 
neighbourhood of the town itself. It is much dreaded 
in the poultry yards, from which it not infrequently 
carries off young birds of all kinds, and being a 
powerful bird on the wing, it is equally able to 
successfully attack poultry of larger size. Its food is 
of a very miscellaneous character, consisting of small 
mammals, birds, reptiles, frogs and inse6ls, though rep- 
tiles seem to afford its main portion. When seen on 
the wing, sailing as it were in the air, with only occasional 
flaps of the wings, it is not unlike the Aura vulture, 
except that the white base of the tail is very conspicuous 
and distinctive, and serves at once to distinguish the 
species from all others. The passage of this bird over or 
near to the poultry yard will always be noticeable owing 
to the peculiar clucking noise set up by the fowls, which 
seem to recognise instinctively an hereditary foe. 
Another species of this genus, U.anthracz'na, has been 
recorded by Prof. CABANIS from the colony, and has, 
apparently on this authority since the bird has not been 
met with by WHITELEY, been included by SALVIN in his 
revised list. It has been included in the foregoing list of 
the hawks of British Guiana on the same authority, 
though the species does not occur in our Museum Col- 
