INTRO DUCHY ON vi

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 ac-

companied by the former character.

In conclusion, I may observe, that the sub-genera into which the Trogons are now sub-
divided, are, as it appears to me, perfectly natural; and I consequently subjoin a synoptical
table, with the species arranged under the sub-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 therty-four, twenty-three of which are inhabitants of America and its

islands, fen of the Indian Islands and India, and one of Africa.