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 witli precision tiie 

 various forms, both European and American, fcmud in the genus, and have 

 brouglit us to satisfactory conclusions in reference to tlieir limitations. 



i\lr. llidgway has lately made a careful revision of the specimens of ^Egio- 

 tlms in the Smithsonian eullection, 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 laud-birds, tliat we may best con- 

 sider the actual species to be two in number, namely, canesccns and linarius, 

 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 

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

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

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

 with Unarms and holboUi ; the winter plumages respectively of the same two 

 races of one species, Hnarws; the latter race, Ivolholli, being the larger or 

 Greenland form. If fvscesmns be darker than summer Unarms from Eu- 

 TO\iQ, it is simply another instance of the darker tints of Arctic American 

 birds as comjiared with European. 



yEgiothus canesccns and c.rUipcs Mr. Piidgway 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 ju-oportions of bill, and jierhaps 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 bill are 

 obscured by the greater length of the bristly feathers around its base in 

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

 New-ton maintains that the same bird will have the biU considerably longer 

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

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

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

 in this respect resembling Alaska specimens of several other FrinijilUdm. 



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

 a critical examination of a series of moi'e than two hundred specimens, in 

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

 clusions. — S. F. B. 



Species and Varieties. 



Common Cn.\RAOTKRS. AduH. Above .streaked with du.sky upon a )iro\\-ni.sh, 

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

 Beneatli whiti-sh, streaked on the sides witli dnsky. An indistinct, lighter super- 

 ciliary stripe. Male. Rump tinged with ro.se-pink. Female. Rump not tinged 

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

 streaked. 



