INTRODUCTION. 
while in others it is so broad as to extend over the whole of the chest. The legs are of a slaty 
blue; and the naked space surrounding the eyes is usually of the same colour with the legs; 
in three species only is it crimson. The bill varies much in colour, and is subject to variation 
in this respect, even in the same species, according to the age of the individual: the general 
distribution of the colouring of the bill seems, however, to be constant. In its proportion to 
the size of the bird, the bill also varies with the age and sex of the individual, but seems to be 
constant in each species in the adult state. It also differs, according to the species, in the 
greater or less convexity of its sides; in the sharpness or roundness of its upper edge; and in 
the smoothness or jaggedness of its cutting edges. 
A. The first section of the Toucans comprehends those in which the upper tail-coverts are 
yellow. In the whole of these the throat is white, with a faint tinge only of yellow; and the 
crimson band by which it is separated behind from the black of the under surface is of small 
breadth. All of them have the upper edge of the bill yellow, and a broad band of the same 
colour surrounding its base, this band being separated by a narrow line of black from the 
adjoining parts of the head and face. This section comprehends three species: 
1. Ramph. culminatus', with the mandibles compressed laterally and wholly black, except 
the culminal and basal bands, which are pale straw yellow. 
2. Rampli. Cuvieri\ with the bill more attenuated than in culminatus the mandibles 
convex and blackish bro^vn, except the greenish yellow culmen and basal belt of 
the same colour, which is bounded before by a broad, and behind by a narrow, 
band of black. 
3. Ramph. erytlirorhynchus ; with the entire bill red, except the yellow culmen and basal 
band, and the black borders of the basal band and cutting margins. 
B. In the second section of the Toucans but one species is comprehended. It is characterized 
either by the total absence of the scarlet pectoral band, or by having it so faint as to be scarcely 
perceptible. The upper tail-coverts are white, exceed the ordinary proportions, and equal in 
length about one half of that of the tail-feathers. The throat is white ; the space surrounding 
the eyes is red, and the eyebds blue. Such are the characters of 
4. Ramph. Toco ; with the bill rich orange, banded at its base and broadly blotched at its 
tip with black. 
C. The third section of the Toucans comprehends two species, distinguished by the upper 
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