MacCallum: I left one M off the list. Malcolm/Mackum/Micum MacCallum, a Scots POW indentured to the Saugus/Lynn Ironworks by Oliver Cromwell in 1651, married a lady named Martha about 1655/6. Martha's maiden name has yet to be learned. Not helping the issue is the fact that their children were recorded under numerous variations of Malcolm and MacCallum. The Mac was dropped by the children.
Low: I'm including this one as a "check your facts really well" item. It has been resolved. I had a John Low married to an Elizabeth Stoddard, both of Hingham in Massachusetts. They married in Marshfield. The two towns were a considerable distance apart for 17th century travel. Further research pointed to an error. I had the wrong couple! The correct pairing was John Low and Elizabeth Howland, both of Marshfield.
Looke: Thomas married about 1646 in Eseex Co., MA. Not only was his wife's maiden name unknown, but researchers weren't sure if she was a Mary or a Sarah.
Lockwood: Ruth, wife of Edmund Lockwood, who arrived with the Winthrop Fleet in 1630, has yet to have her maiden name unveiled.
Livingston: Judith Livingston was believed to be the wife of Henry Barlow of VA and KY. There is no definitive proof of that "fact."
Latham: The paternal line of Frances Latham, "the Mother of Governors," is a bit lacking in maternal detail. Lewis & Elizabeth, John Jr. & ????, John Sr. & Joan, Thomas & Elizabeth, Nicholas & ????. Maiden names or full names are missing in each generation.
Lakin: Margery, wife of Henry, married about 1654 in England. Maiden name unknown.