Several McFarlin's married into the historic Tilson family of Mass. Yes, they are descendants of the Mayflower through the Tilson line. The book "The Tilson Genealogy" by Mercer V. Tilson is on line and you can find your McFarlin ancestors on pages 243,244,245,246,247, 248, and 249. The ancestor Stephen Tilson(Edmund, Ephraim, Edmond) who married Janet Murdock(John Murdock) is the Mayflower connection. They are descendants of John Alden, Priscilla Mullins, William and Alice Mullins, Richard Warren, and Elder William Brewster. Good luck to you in researching your ancestors.