While Wright designed the interior, architect David L. Leavitt is generally credited with the exterior. Manitoga postdates Frank Lloyd Wright's Fallingwater (built in 1936-39), and while the there is some resemblance, the latter was not a direct inspiration. The two Wrights were not related but were acquaintented with each other.  Photo 1 of 9 in The Remarkable Home of Modernist Designer Russel Wright