144 Grinxell, T-mo Races of the Varied Thrush. \_\'% 



dryer interior region of northern Alaska. The Sitkan race is 

 characterized by a predominance of deep browns, restriction of 

 white or Hght markings, and by a shorter and more rounded wing. 

 The northern and interior race has a much grayer and paler 

 coloration, greater extension of white markings, and a longer and 

 more pointed wing. Unfortunately I have no male birds from 

 Sitka, except juveniles ; but three spring males from the Kowak 

 Valley, when compared with late winter males from northern Cali- 

 fornia taken along with females referable to /icFTia, are of a lighter 

 slate color dorsally and slightly paler tawny beneath. The 

 females of this species appear to be much more subject to 

 protective coloration, so-called, than the males, and it is there- 

 fore reasonable to expect climatic variations to be more pro- 

 nounced in the females than in the males, especially when the 

 climate of the snmvicr habitat is of an extreme nature. In the 

 winter home of the Varied Thrushes there is also a ditiferent dis- 

 tribution of the two races, but their latitudinal relation is reversed. 

 Thirty-tive skins from Los Angeles County, California, are all but 

 one referable strictly to nicriiloides^ while the majority of the 

 winter skins from the coast region of central and northern Cali- 

 fornia are near luevia. So that vieruloidcs., although its summer 

 habitat is northernmost, goes farthest south in winter, and its 

 migration route is much the longest. NcEvia apparently has a 

 much shorter migration route, probably at most between the lati- 

 tudes of Sitka and Monterey. The wing-contour seems to offer a 

 criterion by which to judge the length of the annual migration of 

 a bird. By the study of further material I hope to arrive at some 

 more definite conclusions in this regard. 



Now, as to the correct nomenclature of the two forms here 

 described, I have had some trouble. Tiirdus lucviiis of Gmelin 

 is brietiy described from specimens taken at Nootka Sound, Van- 

 couver Island. As this is rather within the Sitkan District, I 

 have applied Gmelin's name to the race breeding in that region. 

 I have not seen the description of Pallas's Turdiis anroreus from 

 Kadiak Island. But the birds from there are probably nearer the 

 Sitkan race, unless they occur only as migrants from further north. 

 For the present, Tardus anroreus may be left as a synonym of 

 ficevia. Orpheus meruloides of Swainson was described from a 



