138 TlMEHRI. 
and it is noticeable that other species all seem to 
be in a state of alarm during the passing flight of this 
bird. 
The two next species to be described present the 
greatest range of variation in colouring to be found in 
any of our hawks. These are the two species of tooth- 
billed kites, Leptodon uncinatus and L. cayennensis, 
which range from a length of 17-24 inches, and seem to 
present, at different stages and ages, all varieties of 
combination of black, white, blue, grey, chestnut, brown 
and yellowish white. They will easily be recognised by 
the characters of their feet and beaks. The tarsal bones are 
short and feathered nearly to the base, and the scales 
behind are reticulated, while the toes are rather short, and 
furnished with long and thin, sharp claws: the beaks are 
strong and thick, and strongly hooked, the nostrils being 
covered with a large scale which gives a linear appear- 
ance to the aperture, while the loral space around is 
bare of feathers. In L, uncinatus the hook of the beak 
is very powerful and produced, recalling the shape of 
that of Rostrhamus, though the base of the beak is 
strong and thick, and quite unlike the thin base in that 
genus. In L. cayennensis the hook is much less pro- 
nounced, but at the curve there is a slightly projecting 
piece which forms a small but broad tooth. These birds 
differ from the typical kites in that their tails are not 
forked, the outer feathers being shorter than the median. 
With regard to the colouring to be met with, the combi- 
nations vary almost with individual birds ; and beyond 
the change from the young and immature to the adult 
stage, it appears that, as in the case of their represen- 
tatives in Europe, the honey-kites, there are seasonal 
