"Iris, Watercolor, Atelier Corpet"
Charles Etienne Corpet was a painter and lithographer. A student of Lesourd de Beauregard, Joanny Maisiat, and Sirouy, he exhibited numerous compositions of flowers and still lifes at the Salon from 1857 to 1903. He was the father of Armand Étienne Corpet (1877-1954). He was an excellent botanical illustrator. The stamp was created by one of the artist's descendants in the 1990s. It bears the stamp in the lower left corner. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato