From Visit Philly:
French sculptor Antoine-Louis Barye helped establish a 19th-century school known as the animaliers, artists who focused on animal subjects, frequently as stand-ins for human emotions. Barye’s portrayal of a lion subduing a serpent illustrates his fondness for dramatic animal battles. The lion, however, is not an ordinary beast. It represents the French monarchy, and the serpent is a universal symbol of evil. Hence this sculpture convinced the French king to name Barye to the Legion of Honor.