Public domain drawing of a mallard duck with his wings spread open. From the turn of his head with his open bill, this fellow looks ready to charm. Is he displaying his wings to attract a lady love or is he perhaps striking a threatening pose to warn other ducks away? Regardless of the intent of the original illustrator, I think this public domain duck drawing would add a bit of fun to any project about birds or ducks.
Lessons From the Vegetable World, printed in 1858, included a number of colorized vegetable and flower images like this one.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.