Vol. 2. (NKw SERIES) OCTOBER^ 1902. No. 4, 
BULLETIN 
OF THE 
WISCONSIN 
NATURAL HISTORY 
SOCIETY 
The Migration of Birds, With Special Reference to Noc- 
turnal Flight — H. A. Winkenwerder, 
MILWAUKEE^ WISCONSIN. 
EVENING WISCONSIN CO., PRINXERS, MILWAUKEE. 
