Margaret -What you have spotted is the names of those who signed the Oath of Allegiance. Many could not write and so had their marks they made. As you noted, some used an X as their signature, but others were able to write an initial or two.On the Palatine ship lists, there are many passengers who have various letters between their names....I know what “X” means, but not the other letters.I am particularly interested in “U” and “N”Examples:
Jacob (E) TaubefishelPeter (B) BarthFrietz (M) MengelTheobald (N) Nabinger
So you may see a first name initial, or a surname initial or both. In some cases a man might use a stylized mark but in any case these letters are simply the representation of their names. If you are interested please see an earlier blog post on Dutch handmarks. It's quite a fascinating subject!