Illustration of juvenile (left), male (center), and female (right), Passenger Pigeons. (AAP042CA). I scanned it from the following publication--now in the public domain:Birds of New York (New York State Museum. Memoir 12), Albany: University of the State of New York.Date of publication : 1910-1914Illustration by Louis Agassiz Fuertes (1874-1927)Information also at Wikimedia Commons.This image is in the public domain, but Flickr does not have a setting for that license--so I have given it the least restrictive Creative Commons License.