Thanks for your reply. I've seen this depositon,which is available with other Dunscombe wills and materials on theRootsweb/Bermuda website.
The Susannah who was a daughter of Thomas and Hannah Jadwyn Dunscombe was born in the 1620-40 span of their childrens' births - about 1636 according to their birth order. I've found nothing more about her. She may have been the ancestor for whom Susannah Dunscombe Ogden Sutton was named - if the latter was indeed a grand-daughter (or great-grand-daughter) of Thomas and Hannah.
There are some listings of Thomas and Hannah's grandchildren on the web (discoverable through Google,LDS, Ancestry, etc.), which I've tried to piece together. In doing so, I've only come across two Susannah Dunscombes - the one above, who was born earlier, and Edward's child whom I mentioned, born later. The only solid (secondary) documentation on the Bermuda Dunscombe family that I've seen is in the Rootsweb collection and Mercer's book.
It would be interesting to see the actual deposition and its original transcription with respect to its "no issue living" assertion, which, if accurate (and honest), would seem to rule out my Susannah as a descendent. But it's curious that all of the numerous descendents of Thomas and Hannah are affirmed to have died before 1705. Samuel's brother, Thomas, had six children, who appear to have included the above Edward who died after 1733.
Putting that aside, here's a possible scenario regarding Susannah: Samuel Dunscombe of Bermuda (1632-1706) had two wives, Elizabeth and Abigail, who died respectively in 1678 and 1684. His children by Elizabeth are all mentioned in his 1706 will, except for Thomas, who had died a few years earlier. Still-living children by Abigail, if any, were excluded. Samuel had one definite child by Abigail - Nathaniel, baptized in October 1679. He, too, may have died before 1706. But Abigail is alleged on the net to have had two others during their five-year marriage - Daniel and Susannah. A young Susannah Dunscombe arrived in Virginia in 1694, perhaps to join Jadwyn cousins. Daniel moved separately to the continent. Both married in New York - Daniel to Helen Swan in 1696, Susannah to Jonathan Ogden about 1699. (Long afterward, Susannah was mistakenly identified as Daniel's daughter by Virkus in his Compendium, causing confusion.) Samuel then testified in his 1705 deposition that, of all Thomas and Hannah Dunscombe's descendents, only he and Thomas, son of Samuel's brother, Philip (who died about 1680), remained, which facilitated the inheritance of Samuel and Elizabeth's children through the will he made three months later, in which he neglected Abigail's surviving children living in New York.