28 Trans. Acad. Sci. of St. Louis 



home, unmindful of temperature. Even in the Arctic 

 regions some birds may be found all winter, where food 

 can be had, species whose food consists of buds, twigs, 

 seeds, berries, or of carrion or refuse ; or those that prey 

 upon other birds. Ptarmigans, Eavens, Gyrfalcons and 

 Owls belong to this dass. 



Of avian nomads several are shown on the chart. The 

 Purple Finches, the Pine Siskins, the Gold Finches may 

 be called nomads, for their stay in any place is of short 

 duration. Few birds are more erratic than the Wax- 

 wings, the Cedar Waxwing of the United States, and the 

 Bohemian Waxwing of the Boreal Zone of both hemis- 

 pheres. 



Many of the nomadic wanderers have a circumpolar 

 distribution. Either the species themselves or nearly 

 related species or subspecies occur in Boreal regions of 

 'America and Eurasia. One hundred and twenty-eight 

 genera of birds are found in both hemispheres, and of 

 the 31 boreal genera of the North American mammals 25 

 are common to Boreal America and Eurasia. As similar 

 facts exist in reference to insects, reptiles and plants, 

 faunal geographers have combined the Palaearctic and 

 Nearctic regions into one grand division under the name 

 of Holarctic Realm. 



A fine example of a bird with circumpolar distribution 

 and nomadic habit is the Pine Grosbeak. In summer it 

 lives in the forests of the Boreal region. In winter it 

 wanders in flocks far and wide, according to circum- 

 stances, extending its movements irregularly into the 

 northern United States, exceptionally as far south as 

 Missouri, where it has been recorded once from 

 La Grange by Susan Johnson, December 3, 1903. 

 Other southern records are Kentucky and District of 

 Columbia. They live on the seeds of trees, coniferous 

 and deciduous, their buds, and are particularly fond of 

 the berries of the Red Cedar and of the seeds of the 



