This is an example of the "lucky" French Angel. This design replaced the crown after the fall of Napoleion III's Empire of France, and was minted from 1871-1906.
Legend has it that Napoleon I carried an earlier version of this coin with him during his wars of conquest across Europe and into Russia. He finally misplaced it on the eve of Waterloo. Augustine Dupre, who designed it, held a copy of the coin as he prayed for his release from the guillotine. It caught the eye of his guard and allowed him to negotiate his escape. Many other claims of cures, intercessions and tragedies averted revolve around the French Angel.
This 1875 20 franc coin features an angel characterizing the ideals of the French Revolution. He represents the Spirit of France as he writes the Consititution. The rooster symbolizes Vigilence. The Empire is symbolized by the fasces, topped by the Liberty Cap, which can also be found on American coinage. (The Walking Liberty image on today's Silver Eagle wears a version of the Liberty Cap.)