Philip Bertram Murray Allan MBE (13 November 1884 – 31 December 1973) was a British lepidopterist and writer who wrote under the initials "O.M.H."
He also ran a publishing house Philip Allan and Company.
He studied at Charterhouse School and went to Clare College, Cambridge.
He worked briefly at the Middlesex Hospital but chose not to pursue medicine and studied history and later became interested in writing, contributing to a dictionary of Latin.
He collected moths and wrote three books and numerous articles.