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Show 1875.] DR. O. FINSCH ON THE SPECIES OF CHRYSCENA. 557 9. Notes on the Fruit-pigeons of the Genus Chryscena. By OTTO FINSCH, C.M.Z.S. [Received September 1, 1875.] In looking over the last number of the Society's ' Proceedings' (January 1875), m y attention was struck by a notice of Mr. Layard, P. Z. S. 1875, p.30,relating to somebirds of the Viti Islands, in which he says:- " By the way, Professor von Suhm and I, after going carefully into the subject, came to the conclusion that the 'Orange Dove' of Taviuni and Lanthala (Chrysama victor, Gould) is a phase of plumage of the ' Green Dove' (Chr. luteovirens)." I regret that Mr. Layard did not tell us more particularly by what facts he became convinced of the identity of these species, as I, being well acquainted with them, do not understand how i.hey can be considered to be phases of one and the same species. I have examined a good series of specimens of Chryscena luteovirens collected by Dr. Graffe at Viti Levu and Ovalau, and have seen all the changes of plumage from the uniform green dress of the first year (the so-called Pt. felicice, Hombr.) to the full-grown stage of the yellow plumage. This latter is, no doubt, that of the very old bird, which is likewise distinguished by a peculiarity in the structure of the feathers not to be found in any other member of the genus Ptilonopus. The small feathers, with exception of those of the head in Chryscena luteovirens, are remarkable for their narrowed cylindrical form, reminding one in some respects of those in Xipholena. But this structure is not to be found in Chryscena victor at all; so that if one were to take the structure of the feathers solely as a distinguishing generic character of Chryscena, C. victor could not be placed in the genus. But, as I have shown already (P. Z. S. 1873, p. 733, foot-note), the genus Chryscena differs from Ptilonopus chiefly in having no shortened and narrowly pointed first quill. In this character, as well as in the shortness of the wing, C. victor agrees very exactly with C. luteovirens; so that of their generic relationship there can be no doubt. But C. victor does not possess the peculiar feather-structure of C. luteovirens. Instead of the cylindrical structure of C. luteovirens, the feathers of C. victor are remarkable for the length and laxity of their rhaches, which resemble those of the Parrot-genus Coryllis (Loriculus), so that the upper tail-coverts project a little over the tail-feathers. N o w if C. luteovirens were only a phase of plumage of C. victor, this could be only in relation to age, and consequently C. luteovirens would have to be regarded as the younger bird. But the structure of its feathers shows a peculiarity which can only be attained in the fully adult bird; and there cannot be the slightest doubt that C. luteovirens would never lose this extraordinary character of feathers and again assume a structure of feathers which comes nearer to that of the young state. I need hardly remark that the coloration in the two species is totally different, being in C. luteovirens, in mature state, dark yellow, and in G. victor deep orange- |