WILSON WARBLEK. 127 



and only one instance of its being' noted in the West Indies— an acci- 

 dental occurrence on the Barbados," April 30, 1873. 



Sj.)j'h)(/ rtilg ration. — The Wilson warbler has never been reported at 

 any point below the hundred-foot contour on the United States coast 

 from the Sabine River to Charleston, S. C. It is practically^ unknown, 

 even as a migrant, in the entire Austroriparian zone, from the north- 

 eastern corner of Louisiana to Virginia. Just above this district it 

 begins to be known, as at Shellmound, Miss., Rising Fawn, Ga., 

 Chester County, S. C, and Raleigh, N. C, but it is rare east of the 

 Alleghenies south of Washington. The principal migration route is 

 along the mountain chain and for the most part on its western slope. 



During the period of spring migration a part}^ of the Biological Sur- 

 ve}^ spent several weeks in northern and eastern Yucatan. The}^ saw 

 no Wilson warblers, although they covered the w^hole time during 

 which the species passes from Costa Rica to the eastern United States, 

 and the country was full of other migrating warblers. Two migra- 

 tion routes are open to the individuals of this species that travel between 

 Costa Rica and the Alleghenies. They can keep on the highlands north- 

 westward to eastern Mexico, and pass thence north to Texas and north- 

 east to the Alleghenies — a route that would be entirel}^ b}^ land, and that 

 would explain in a perfectly satisfactor}^ manner the absence of the 

 species from Yucatan, the coast of Honduras, the whole of the south- 

 eastern United States, and the AVest Indies; or they may travel from 

 Costa Rica through Guatemala to Tabasco, and then across the Gulf 

 of Mexico to the eastern United States. A comparison of the dates of 

 migration will aid in deciding which of these routes is emplo^^ed. Some 

 records of the species south of the United States are as follow^s: Fron- 

 tera, Tabasco, seen occasionally in earl}^ March, 1900; near Teapa, 

 Tabasco, several noted early in April (one specimen April 5); Mot- 

 zorongo, Vera Cruz, March 11; Jalapa (l-,400 feet), Vera Cruz, March 

 30 and 31 and April 5, 1897; Las Vigas (8,000 feet), Vera Cruz, April 

 21, 1897; Tamaulipas, March 26 to May 10, 1888; Nuevo Leon, March 

 22, 1902. The following Texas dates of earliest spring arrivals are 

 not numerous, but they are enough for the present purpose: Lower 

 Rio Grande, April 26, 1878; Victoria County, April 30, 1887; San 

 Antonio, April 30, 1889, and April 25, 1890; Austin, May 2, 1890; Dal- 

 las, Ma}^ 3, 1898, and May 3, 1899. This is one of the ver}^ few sets of 

 Texas dates representing a direct migration northward from the lower 

 Rio Grande to northern Texas. The dates of earliest arrival to the 

 eastward are: Shellmound, Miss., April 15, 1892; Helena, Ark., April 

 30, 1897; St. Louis, May 1, 1881, April 29, 1885, and May 2, 1887; Ris 

 ingFawn, Ga., May 1, 1885; Asheville, N. C, May 7, 1891; Blooming- 

 ton, Ind. , May 8, 1886. According to these dates the birds of the Alle- 



^Salvin, Ibis, p. 334, 1873. 



