Astragalinus tristis
Lakeside
1907
July 24.  
  A goldfinch singing on wing at the height of the breed-
ing season moves through the air in a perfectly level plane and 
hence in a manner very different from that of its ordinary flight.
Sometimes it describes a large and irregular circle, sometimes
proceeds almost or quite straight. Whatever be its course it usu-
ally flies above the tops of the tallest trees and beats its wings
continuously but rather feebly or loosely something after the man-
ner of a butterfly. All the while it sings continuously and very
sweetly its chanting strain. This ended it pitches down to the
nearest tree or telegraph wire to rest for a time before rising
and singing again. I have repeatedly seen the singing bird close-
ly followed by another which did not sing, but which flew exactly
like the first. In no instance, however, have I been able to de-
termine the sex of the second bird.