88 The Ornithology of Chester County 



Berwyn : 



Arrival Apr. 21 (1893) May 12 (1914) ; ave. 

 25 yrs. May 4. 



Common Apr. 29 (1893) May 17 (1902- 

 1917) ; ave. 23 yrs. May 10. 



Bulk departure Aug. 31 (1903) Oct. 7 (1895- 

 1897) >* ave - *3 y rs - Sept. 21. 



Last seen Sept. 18 (1891-1901) Oct. 26 

 (1900) ; ave. 20 yrs. Oct. 6. 



179. Vireosylva philadelphica Philadelphia Vireo. 

 Rare transient. Josiah Hoopes captured specimens 

 at West Chester, Sept. 30 and Oct. 6, 1891 (Stone, 

 Bds. E. Pa. and N. J., 126) ; and I shot an adult 

 female (No. 685, coll. F. L. B.) Sept. 19, 1898, at 

 Berwyn (Wils. Bull., 24, 7) ; the above appear to 

 be the only records for the county. 



1 80. Vireosylva gilva gilva Warbling Vireo. Tol- 

 erable common summer resident. W. L. Baily found 

 newly made nest at Paoli, May 18, 1891. 



Berwyn : 



Arrival Apr. 30 (1906-1908) May 12 

 (1914) ; ave. 14 yrs. May 7. 



Common May 8 (1916) May 15 (1915); 

 ave 3 yrs. May n. 



Departure Sept. 4 (1913) Oct. 7 (1910); 

 ave. 8 yrs. Sept. 19. 



181. Lanivireo flavifrons Yellow-throated Vireo. 

 Not common summer resident. W. S. Hall took a 

 set of eggs, Willistown, July 2, 1884; and the 

 writer found two nests: Valley Forge, June 11, 

 1885, and Berwyn, June 18, 1899. 



Berwyn: 



