Augustin François César Prouvençal de Saint-Hilaire (4 October 1779 – 3 September 1853), French botanist and traveler, was born at Orléans, France, on 4 October 1779.
A keen observer, he is credited with important discoveries in botany, notably the direction of the radicle in the embryo sac and the double point of attachment of certain ovules.
He also described two families, the Paronychiae and the Tamariscinae, as well as many genera and species.