298 
THE YELLOW-BILLED CUCKOO. 
third longest, the primaries tapering. Tail long, graduated, of ten feathers, 
which are rather narrow and rounded. 
Upper mandible brownish-black, yellow on the margin towards the base ; 
under mandible yellow. Iris hazel. Feet greyish-blue. The general colour 
of the upper parts, including the wing-coverts and two middle tail-feathers, 
is light greenish-brown, deeper anteriorly. Primary quills with the inner 
webs brownish-orange. Tail-feathers, excepting the two middle ones, black, 
the next two entirely black, the rest broadly tipped with white, the outer- 
most white on the outer web. The under parts are greyish-white. 
Length 12J inches, extent of 
wings 1G ; bill along the ridge 1, 
along the gap 1L 
Adult Female. 
The female differs very little 
from the male in colouring. 
In a female of this species pre- 
served in spirits, the length to the 
end of the tail is Ilf inches ; to 
end of wings 9, to end of claws ; 
extent of wings 15h ; wing from 
flexure 5 t 8 2 ; tail 5 T V 
The roof of the mouth is flat, 
and covered with a transparent 
skin, as in Goatsuckers and Owls ; 
the upper mandible very narrow 
towards the end, and slightly 
concave, with three longitudinal 
ridges ; the posterior aperture of 
the nares oblong behind, linear 
before, only 4 twelfths long ; the 
width of the mouth 7 twelfths ; the 
lower mandible channelled. The 
tongue is very slender, 10 J twelfths 
long, emarginate at the base, with 
long slender papillas, its breadth at 
the middle only li twelfths, horny 
in the greater part of its length, 
with the edges lacerated, the tip 
rather acute and slight. CEso- 
phagus, ab c, 3 inches 7 twelfths 
