Vi I N T R O D U C T I O N .
only a single species has yet been discovered. I t is in ’South America, however, that we find
the greatest number of species, and those of the most exquisite plumage : nor is this a ll; for it
will be further observed that, in accordance with the great geographical distribution thus
pointed out, there exist certain characters common to the species inhabiting each region,
which, although not very apparent to the unpractised eye, constitute the basis of generic
subdivisions, and doubtless have an influence upon their habits and manners. Between the
American species, and those inhabiting India and Africa, we not only find this broad line of
distinction, but discover moreover that the birds of each country are themselves naturally
resolvable into certain minor groups, each possessing its peculiar characters, and each as
different in habits as in form.
The beautiful species of the group to which the sub-generic title of Calurus has been
applied, distinguished by a redundancy of flowing plumage, are not, as may be expected, so well
fitted for flight, or for taking their prey on the wing, as are the more closely-plumed species to
which the generic name of Trogon is now restricted; accordingly Mr. Natterer informs me that
the gorgeous birds of the former group tenant the topmost branches of the loftiest forest trees,
clinging beneath them like Parrots, and feeding more exclusively on fruits and berries; while
on the other hand, Mr. W. S. Mac Leay states that the singular Trogon inhabiting Cuba, (the
only example of the sub-genus Temnurus) which approximates to the Woodpeckers in the more
lengthened form of the bill, in the rigid character of the outer tail-feathers, and in the spotting
of the wings, approaches these birds also in its habits, giving a preference to the holes of
trees rather than to the branches, from the hark of which it procures the larvae and various
insects which constitute its food.
The habits of the Old World species are unfortunately much less known than those of
their American relatives. From the more robust form of their hill and their wide gape, I am
inclined to suspect that they feed even still more exclusively on insects than on fruits; independently,
however, of the greater strength of the bill, the non-serration of the edges of the mandibles,
and the half-denuded face, they may at all times be distinguished by the rich brown
colouring of the backs of the males, and by the entire absence of bars across the outer tail-
INTRODUCTION. vii
feathers. With respect to the brown colouring of the plumage, there are, it is true, one or two
exceptions to the rule, but none to the absence of the barring of the tail-feathers, when accompanied
by the former character.
In conclusion, I may observe, that the sub-genera into which the Trogons are now subdivided,
are, as it appears to me, perfectly natural ; and I consequently subjoin a synoptical
table, with the species arranged under the suh-genera which have been proposed by Mr. Swain-
son, while at the same time in the body of my work I retain the generic name of Trogon,
universally applied to the whole family.
Previous to the commencement of this Monograph, the number of described species
amounted only to twenty-two ; to these I have added and characterised twelve others new to
science ; among which are three additional species of the sub-genus Calurus, of which only two
were previously known, and those confounded under one name. The total number, therefore,
of species now known is thirty-four, twenty-three of which are inhabitants of America and its
islands, ten of the Indian Islands and India, and one of Africa.