​From Wikipedia, the free encyclopedia Pamela Ann "Pam" Ferris (born 11 May 1948) is a German-born Welsh actress. She is best known for her starring roles on television as Ma Larkin in The Darling Buds of May, as Laura Thyme in Rosemary & Thyme, and for playing Miss Trunchbull in the movie Matilda. She also played the part of Aunt Marge in Harry Potter and the Prisoner of Azkaban. Description above from the Wikipedia article Pam Ferris, licensed under CC-BY-SA, full list of contributors on Wikipedia.