Research elsewhere may suggest that this is indeed Arthur Williams (not Wallace).
An Arthur Williams, born in Toronto, Canada on or about 1 September 1900, was killed in action in French Morocco on 10 November 1942, while serving with the Foreign Legion (Unit 2e, régiment étranger d'infanterie (2e REI)).
This Arthur Williams is buried in French Military Cemetery at Marrakech (Plot H row 15 grave number 327).
Can anybody connect these details with the gentleman in the photograph? And does anyone know more about this fallen hero (see photograph of the grave).