106 ORTHOGENETIC EVOLUTION IN PIGEONS. 



My studies of the behavior, voice, and color-pattern of several of these species 

 leave no doubt that some of them have made a much wider departure from ances- 

 tral conditions than have others. Columba unidncta and C. palumbus seem to stand 

 nearest the turtle-doves. Through the courtesy of Dr. Dearborn, of the Field 

 Columbian Museum, Chicago, I have been able to examine the skin and to have 

 a figure (pi. 46, fig. B) prepared of the very rare C. unidncta. The wing of this dove 

 has more feathers than the wing of the turtle-dove, but it is clear that the feathers 

 have the turtle-dove pattern blackish centers with pale-gray edges. The feather- 

 shafts, too, are quite black. The feathers of the rump and upper tail-coverts are 

 edged like those of the wing, though not so strongly or prominently. This seems to 

 me to be a very important connecting link between Turtur and Columba. 



The color of the young of this species has recently become known from a descrip- 

 tion by Mr. D. Seth-Smith, 10 who says: 



"The top of the head has each feather minutely striped with blackish and tipped with 

 rufous brown or whitish; the feathers of the nape and mantle have towards the tip a narrow 

 line of blackish 11 fringed with white, the rump and upper tail-coverts are gray, fringed with 

 white, the lesser wing-coverts becoming black towards the tip n and being broadly tipped 

 with chestnut-brown." 



Columba palumbus best shows its relationship with the turtle-dove in its neck- 

 mark (text-fig. 6, Vol. II). Like other species of Columba, it has a greater number 

 of rows of modified neck-feathers 11 rows in this case but the light-colored tips 

 are confined to the lower 6 rows, which correspond to the turtle-dove neck-mark 

 (this shown in color, pi. 48, fig. A). 



In the young 12 of the wood-pigeon I find the wing-coverts of the first plumage 

 are all edged with light brownish-yellow, while the second feathers show no such 

 edging. The neck-spots have not yet appeared, or at most they are present in only 

 a few feathers. 



Columba gymnopthalma of Curagao and the coast of Venezuela has neck-feathers 

 that suggest (pi. 48, fig. B) the European wood-pigeon (C. palumbus), the Euro- 

 pean turtle-dove (Turtur turtur], and the white-crowned dove (Columba leuco- 

 cephala) of the West Indies. 



Salvadori (page 278) gives an imperfect or incomplete description of the plu- 

 mage: "Lower part of the hind neck (side and back) with light grey and dark grey 

 narrow bands above, and with reddish opaline and blackish narrow bands lower 

 down." Comparing this with Temminck's figure, 13 this means that the feathers in 

 the region corresponding to the neck-spot in the wood-pigeon are edged with narrow 

 dark crescents, similar to the white-crowned pigeon (C. leucocephala) , but these dark 

 crescents are followed within by lighter (whitish) crescents. Temminck says: "Two 

 zones or crescents mark the tips of the feathers." 14 



Ibis, July 1907, page 464. 



11 This line of blackish next to the apical mark reminds of the same subapical or subterminal mark in the tam- 

 bourine-dove, in Geopelia, etc. 



"Three specimens in their first molt were obtained from Mr. F. Chatwin, of Dover, England, and a comparison 

 of the molted and unmolted feathers of these birds is the basis of these remarks. 



" Temminck and Knip, Pig., I, 2d fam., p. 48, pi. xvm. 



"Temminck says there is a black spot beneath the ear-coverts, but, as no such spot appears in his figure, I assume 

 tint ho is confounding this bird with another species our white-winged pigeon (Melopelia leucoptera). 



