Old Master who painted pretty ladies on seaside?
They are frolicking, wearing ruffled dresses
I suppose you're either referring to the works of Pierre Auguste Renoir or those of Claude Monet. Childe Hassam is also another legendary painter who was fond of using this theme. Check out some beautiful paintings done by Claude Monet at http://www.moodbook.com/history/impressionism/claude-monet-paintings.html.