Erastus Mcmains, wife Mable Farrar Mcmains, children James, Carl, Dewey Dan, Lucille, and Elizabeth lived in Minnesota, primarily in Hennepin County. Erastus died 1936, Mable 1937, both in Hennepin County. I know they moved from Iowa, to Wisconsin, and finally to Minnesota. They arrived in Minnesota sometime after 1904, and no later than 1915.
In the 1920 census, they were living at 3122 N. 43rd Street, Minneapolis.
My research notes can be found on my Mcmains Research and Collaboration Site, http://freepages.genealogy.rootsweb.com/~hewes/indes.html From the "Mcmains Hub" page, click on "Research Notes for Erastus Mcmains".