The tendencies in the evolution of these insular populations of _Gallicolumba_ include a reduction of sooty-black on the head and a reduction of coppery gloss on the back of the male and the reduction of malelike plumage in the female. _G. rubescens_ of the Marquesas Islands is smaller and darker. It retains the coppery gloss on the back and has, in addition, a white bar on the tail and one on the wing. On the basis of color and structural characters, it is apparent that this superspecies of _Gallicolumba_ has evolved from a center of evolution in the region of New Guinea (as shown in figure 14) with a colonization of Micronesia, from which (probably from _G. x. kubaryi_) an invasion of eastern Polynesia occurred establishing _G. erythroptera_ in the Society and Tuamotu islands, although it is also possible that _G. erythroptera_ may have reached Polynesia by way of a more direct route from Melanesia. Such a pathway of colonization as that just described is not unusual since representatives of other genera including _Acrocephalus_, _Myzomela_, and _Zosterops_ may have followed similar paths of dispersal from Micronesia into Polynesia. Apparently a population isolated in the Marquesas has evolved the distinctive _G. rubescens_. =Caloenas nicobarica pelewensis= Finsch Nicobar Pigeon _Caloenas nicobarica_ var. _pelewensis_ Finsch, Journ. Mus. Godeffroy, 8, 1875, p. 159 (in reprint p. 27). (Type locality, Palau.) _Caloenas nicobarica pelewensis_ Mathews, Syst. Avium Australasianarum, 1, 1927, p. 77 (Pelew); Hand-list Japanese Birds, rev., 1932, p. 188 (Palau); Peters, Check-list Birds World, 3, 1937, p. 139 (Palau); Hand-list Japanese Birds, 3d ed., 1942, p. 210 (Babelthuap, Koror); Mayr, Birds Southwest Pacific, 1945, p. 291 (Palau); Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 62 (Garakayo). _Caloenas nicobarica_ Salvadori, Ornith. Papuasia, 3, 1882, p. 211 (Pelew); Wiglesworth, Abhandl. und. Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 57 (Pelew). _Caloenas pelewensis_ Salvadori, Cat. Birds British Mus., 21, 1893, p. 618 (Pelew); Bolau, Mitteil. Naturhist. Mus. Hamburg, 1898, p. 69 (Palau); Matschie, Journ. f. Ornith., 1901, p. 113 (Palau); Reichenow, Die Vögel, 1, 1913, p. 328 (Palauinseln); Takatsukasa and Kuroda, Tori, 1, 1915, p. 52 (Pelew). _Caloenas nicobaricus pelewensis_ Kuroda, in Momiyama, Birds Micronesia, 1922, p. 53 (Pelew). _Geographic range._--Micronesia: Palau Islands-Babelthuap, Koror, Garakayo. _Characters._--Adult: A large heavy-bodied pigeon with head, neck, and upper breast blackish; rest of plumage metallic bluish-green with coppery sheen; wings glossy green; tail and under tail-coverts white; feathers of hind-neck long and lanceolate; bill heavy and slightly hooked with lump at base.