IO Cooke., Routes of Bird Migration. \_}&n. 



many thousands of these birds in the northeastern United States 

 that they could not all pass through the Gulf States unnoticed, and 

 so one is led to believe that having passed to the southern end of 

 the mountains, they start at once on their journey across the Gulf, 

 flying over the Gulf States. Since they are also unknown in the 

 lower regions of Yucatan and Honduras, but are known in 

 the higher regions of Guatemala, the same line of reasoning 

 leads to the belief that the birds do not alight as soon as they 

 reach the south shore of the Gulf, but continue their flight to the 

 mountains beyond. The case is not so clear on the south side of 

 the Gulf as on the north, since so few competent ornithologists 

 have visited this section, and since the birds' stay would be 

 limited to the few days of passage in migration spring and fall. 



Future observations may show that a few Canadian Warblers 

 occur in northwestern Florida, and also along the coast of the 

 Bay of Campeche, but as the record now stands it indicates that 

 the principal route of migration of the Canadian Warblers of the 

 northeastern United States is from the southern Allegheny Moun- 

 tains across the Gulf of Mexico to the highlands beyond. 



Along the route thus outlined it seems probable that the indi- 

 viduals from the northeastern United States of the following 

 species pass in their migrations : 



Olive-sided Flycatcher (Nuttallornis borealis). 

 Yellow-bellied Flycatcher (Empidonax Jlaviventris). 

 Philadelphia Vireo (Vireo fhiladelfkicus). 

 Blue-winged Warbler {Helminthophila finus). 

 Golden-winged Warbler {Helminthophila ckrysoptera). 

 Bay-breasted Warbler (Dendroica castanea). 

 Canadian Warbler ( Wilsonia canadensis). 



If the southern part of the above route is carried eastward to 

 . include Honduras, it agrees with the present records of the east- 

 ern individuals of the Chestnut-sided Warbler (De?idroica pensyl- 

 vanicd). 



If at the same time the northern part is supposed to start from 

 the western slope of the Alleghenies, the route accords with the 

 known facts concerning the migration of the eastern individuals of 

 the Tennessee Warbler {Helminthophila peregrina). 



If the southern end is shortened, making the flight from the 



