Lecture by Advolly Richmond. Thomas Birch was a trained botanist, and head gardener at Orwell Park, Ipswich, before travelling to the Gold Coast. He became part of the international network of correspondents and plant collectors relied upon by the Royal Botanic Gardens at Kew. Kellogg College, 62 Banbury Road, Oxford. 6.30 p.m., for lecture at 7 p.m. Members £5/guests £8, including a glass of wine or juice; pay at door.