492 NORTH AMERICAN BIRDS. 



(1861, 375 ; 1863, 40 ; and 1869, 180) being models of ornithological criti- 

 cism and discussion. His labors liave enabled us to define with precision the 

 various forms, botli European and American, found in the genus, and have 

 brought us to satisfactory conclusions in reference to their limitations. 



Mr. liidgway has lately made a careful revision of the specimens of ^gio- 

 thus in the Smithsonian collection, and with a general concurrence in the 

 conclusions of Dr. Coues in regard to the differences observable, he sug- 

 gests, as an application of the laws more recently verified by him and myself 

 in our examination of the North American land-birds, that we may best con- 

 sider the actual species to be two in number, namely, canescens and Unarms, 

 ranging the other forms under these, either as geographical races or as sea- 

 sonal stages. Bearing in mind the general law that the more boreal or 

 Greeidand-born specimens should be larger than the more southern or Con- 

 tinental, and that the peculiar dark plumage of fuscescens and rostratus 

 only occurs in summer breeding specimens, he considers these as identical 

 with linarius and holhdlli ; the winter plumages respectively of the same two 

 races of one species, Unarms; the latter race, IwlholU, being the larger or 

 Greenland form, li fuscescens be darker' than summer linarias from Eu- 

 rope, it is simply another instance of the darker tints of Arctic American 

 birds as compared with European. 



j^giothus canescens and exiUpes Mr. Eidgway considers as the Greenland 

 (larger) and Continental (smaller) races of one species, which perhaps do not 

 differ so much with season as do those of Unarms. The differences in the 

 size and proportions of bill, and perhaps of feet, Mr. Eidgway does not think 

 of much importance, as great variations are observable in this respect in 

 specimens from the same locality, and the actual differences of the liill are 

 obscured by the greater length of the l^ristly feathers around its base in 

 winter, making it appear considerably shorter. Indeed, Professor Alfred 

 Newton maintains that the same bird will liave the bill considerably longer 

 in summer, after living on soft insect food, and shorter in winter when worn 

 down by use on hard seeds. Mr. Eidgway finds, too, that specimens of Una- 

 rms from Kodiak differ in a much longer and more slender bill than usual, 

 in this respect resembling Alaska specimens of several other FringilUclK. 



The following synopsis expresses Mr. Eidgway's views as indicated above : 

 a critical examination of a series of more than two hundred specimens, in 

 the collection of the Smithsonian Institution, being the basis of his con- 

 clusions. — S. r. B. 



Species and Varieties. 



Common Characters. Adult. Above streaked with dusky upon a browni.sh, 

 or brown and whitish, ground ; wing-coverts tipped with whitish or pale brown. 

 Beneath whitish, streaked on the sides with dusky. An indistinct, lighter super- 

 eihary stripe. Male. Rump tinged with rose-pink. Female. Rump not tinged 

 witli pinkish. Juv. Without any red, and with the whole lower parts thickly 

 streaked. ( 



