From The Arthur Conan Doyle Encyclopedia
Howard Marion-Crawford (17 january 1914 - 24 november 1969) was a British actor who played Sherlock Holmes in 1948, in a BBC radio show: The Adventure of the Speckled Band, with Finlay Currie as Dr. Watson. But he is most wellknown for his role of Dr. Watson in the TV series Sherlock Holmes in 1954-1955 with Ronald Howard as Sherlock Holmes.
He was descendant of Gabriel Marion, from Poitou in France, who settle in USA in the 1690s. 
- The Genealogical Adventure and Incredible Heritage of Dr. Watson, by F. Burkle-Young.