MF5 John Howland Vol 23 part. 2 p 199 says that #292 Ruth Thomas (1731-1807), d/o Mary Bosworth (#70) and her husband Richard Thomas, married Elisha Bliss (1732-1777), s/o Elisha and Margaret (Newman) Bliss.
It doesn't say anything about her marrying Barton. So if it says she married Barton in Part 1, The Mayflower Soc. has corrected itself in part 2.