Transcriber's Notes:
Obvious printer's errors have been repaired, other inconsistent spellings have been kept, for example inconsistent use of hyphen (e.g. "age-classes" and "age classes") and diacritical mark (e.g. "Zool." and "Zoöl.")
About This Book
The paper analyzes a sample of migratory birds killed after striking a tall broadcasting tower near Topeka, presenting species accounts, weather and tower descriptions, and detailed measurements. It evaluates sample randomness, numbers of migrants, and differential migration by sex and age using statistical methods, and relates molt and size differences to migratory status. Methods for processing specimens and computations of longevity and survival are described, historical incidents are reviewed, and the authors argue that repeated, geographically varied sampling would yield robust evidence about nocturnal migration and collision mortality.