ROUTES OF MIGRATION. 13 



Blue-wmged warbler {Helminthophila pinus) . 

 Nashville warbler {Helminthophila rubricapilla). ' 

 Tennessee warbler {Helmintho2)hila peregrina). 

 Wilson warbler ( Wilsonia pusilla) . 



It IS probable also that this route is used by many individuals of 

 the following- species: 



Cerulean warbler {Dendroica cerulea). 

 Chestnut-sided warbler {Dendroica pensylvanica) . 

 Blackburnian warbler {Dendroica hlackhurnix) . 

 Mourning warbler {Geothlypis Philadelphia). 



It seems probable that not all birds in their migrations north across 

 the Gulf of Mexico alight as soon as they reach the coast of the 

 United States. How far they penetrate into the interior before they 

 descend is not known, but the latitude reached probably approxi- 

 mates the northern edge of the Gulf strip of the Austroriparian life 

 zone — that is, slightly north of the latitude of the northern boundary 

 of Florida. More or less strong reasons exist for believing that sonjie 

 individuals of each of the following species sometimes fly inland befoi-e 

 alighting: 



Black and white- warbler ( Mnioiilta varia ). 

 l^ashyille warbler {Helminthophila rubricapilla). 

 Yellow warbler {Dendroica sestiva). 

 Magnolia warbler {Dendroica maculosa). 

 Cerulean warbler ( Dendroica cerulea) . 

 Cbesinwi-^liXed warbler Dendroica 2)ensylvanica). 

 Bay-breasted warbler {Dendroica castanea). 

 Blackburnian warbler {Dendroica hlackhurnix) . 

 Mourning warbler ( Geothlypis philadel2)hia) . 

 Yellow-breasted chat {Icteria virens). 

 Wilson warbler ( Wilsonia pusilla) . 

 Redstart {Setophaga ruticilla). 



OCCASIONAL ROUTES TO OR THROUGH CUBA OR YUCATAN. 



Mention should be made of two other possible routes that have not 

 yet been noticed — one from Cuba to Yucatan, the other from Cuba to 

 South America. It is undoubtedly true that certain day-migrants (tt.e 

 swallows, for instance) cross between Cuba and Yucatan, but of the 

 night-migrants, such as the warblers, there seems at present no proof 

 that any use this as a regular path of migration. The fact that a com- 

 paratively small number of species of warblers are found as regular 

 visitors to both Cuba and Yucatan would create a presumption against 

 this route being much used, while some of the warblers certainly do 

 not follow it. The three following lists make these points clearer. 



SPECIES THAT OCCUR REGULARLY IN BOTH CUBA AND YUCATAN. 



Black and white warbler {Mniotilta varia). 

 Parula warbler ( Compsothlypis americana) . 



