Mrs. Hudson; however, in the story "A Scandal in Bohemia", Holmes' landlady is named Mrs Turner:"When Mrs. Turner has brought in the tray I will make it clear to you. Now," he said as he turned hungrily on the simple fare that our landlady had provided, ..."Martha (only) is the name of the maid in the short story 'His Last Bow,' and some have speculated that this Martha and Mrs. Hudson are the same person. Anything further is outside the realm of the Sir Arthur Conan Doyle stories.