380 



grain. In orchards they averaged 4V2 times as numerous to the 

 unit of area as in fields of grain, 2,471 to the square mile — giving 

 a density ratio of 3.84; but the acreage in orchards from which the 

 birds were identified was so small that all the orchard birds to- 

 gether amount to only 2 per cent, of the whole number observed. 

 Among native trees and shrubbery, birds were much less abundant 

 than among fruit trees, and the density ratio for these situations 

 was about 2.25. 



By way of further illustration of the application of this quanti- 

 tative method to the subject of local distrilnition, I will present some 



