[The format used by Morse is very confusing. Comments have been inserted in brackets to indicate the parent/child links he indicates with his numbering system.]
[p. 20:]
Samuel [child 9 of Daniel and Lydia, family on p. 21], [born] 12, (3,) '61, d. March 2, 1704, m. Deborah ---.
Samuel [child 4 of Jonathan and Mary Barbour, family on p. 22], b. 10 Aug 1676, m. Bethiah ---.
[p. 21:]
Samuel [child 9 of Daniel and Lydia)] wife Deborah ---, died Oct. 5, 1719, resided at Sherborn. (Children Samuel 1687 [child 1, children listed on p. 22], Eleazar 1688, ...)
[p. 22:]
Samuel [child 4 of Jonathan and Mary Barbour] w. Bethiah, m. (2) 13 Jan 1712-13 Mary Cook. (Children: Edmund 1695, Margaret 1699, Elizabeth 1702, Andrew 1713, Abijah 1718, Nathan 1720, Mary 1725, Jonathan 1729)
Samuel [child 1 of Samuel and Deborah] w. Mary Cook, m. 1712-13, d. November 20, 1787, r. Needham. (Children by Mary: Deborah 1715, Samuel 1717, Mary 1720, Joseph 1723, Miriam 1725, Amos 1729, Joseph, 1727, Benj. 1731, Sarah 1734.)
[Morse has clearly given the marriage to Mary Cook to two different Samuel Morses. The marriage is recorded in Sherborn and is followed by the birth of Andrew in Sherborn to Samuel and Mary in Oct 1713. So it appears Mary Cook was the second wife of the Samuel Morse born in 1676. The other Samuel and Mary Morse do not have a child until Aug 1715 in Needham, which is 2 1/2 years after the marriage to Mary Cook, so this is probably a different Mary...]