Thanks for your response. In my earlier post, it was not my intention to state that Edna Shannhouse, or anyone else for that matter, was wrong simply because we don't know the original sources. I am merely trying to prove the information just as I would any genealogical data that I did not personally collect from primary records. So far, I've had no luck in this instance.
On the other hand, I do not have any specific reason to think our Morrisettes are descended from the Manikin Town lines, either. It has just occured to me that it is a possibility worth investigating.
Many of the given names common in our early generations were the same as the common names in the Manikin Town families during the same period, merely anglicized. In addition, this was about the same time frame that some of the Manakin Town Morrisettes began anglicizing their names, as well as moving into the parts of the country that "our" Morrisettes were first known to be in. Based soley on times and locations, it is a feasible theory.
Basically, until I can find hard proof of an original ancestor in America that connects with the later generations that are believed to be the Thomas Morrisette line, I am willing to explore all possibilities.