birds of a feather - 1962

Enid Collins of Texas 1962 "birds of a feather" box bagheight - 5 3/4"    width - 11 1/8"    depth - 2 3/4"
 
 

 As far as I know, this is the only "birds of a feather" box bag design. It likely relates to the proverb "birds of a feather flock together," but not sure of the context in 1962.