I was aware that Hughenden had been called Hitchenden, etc., but still can't find any reference to it, sadly, although the will continues to get easier to read.
Regarding the reasons for no information about Ruth/Mary/?'s baptism or marriage, I'd say that whilst there could easily be gaps due to the reasons you stated, I have other records for West Wycombe, where if the records had been destroyed I would expect to have found none at all.
Also, while it would appear that there are no records of the baptisms of four of Robert Biscoe's children, their full birth dates
are recorded. Someone was clearly being thorough enough to make note of the details of their births. This was during the Commonwealth Gap.
I can't find any evidence that this particular clutch of Biscoes moved around much at this stage, except to the next parish occasionally.
I don't understand why I can't find a record of Ruth, but, since we have records of Moses her brother, we at least know her father's name. Who
his parents were, hard to say with absolute certainty, but his daughters' names being identical to those of Robert of Wycombe's wife and mother is indicative of
some link, imo, given the common family naming conventions of the time (although these were not always slavishly adhered to). Plus, as we know, Susan had links to Hughenden herself.
I can't locate the Westminster Biscoes on the pedigree I have, but then not all descendants are on it. Out of interest, does a little "bird's foot" on a pedigree indicate that that individual has descendants not included on that pedigree? Given the origin of the word "pedigree", I did wonder.
(the pedigree can be found here, by the way:
http://ia600302.us.archive.org/0/items/pedigreeoffamily00smit/pedigreeoffamily00smit.pdf . I know you are researching the Lanes, but it might still be useful or of interest). There is a mention of a Thomas Biscoe of Swanbourne on page 3.
I wasn't aware of a Berkshire link, but 1683 would make the Hughenden Moses 28 when he married (if it is him), plus his wife was called Mary. Incidentally, John (d. 1764) Stallion had a daughter, Martha, who married a Floyd and had three children, William, Mary and Martha. She (Martha Sr.) predeceased her father, which is why her children are mentioned on John's will.
That said, the Berkshire Moses could be a different one, as I had been under the impression that Moses's wife's maiden name was Ginger, since he mentions his brother-in-law John Ginger.
I've ordered the Rev. John Biscoe's will, which I'm hoping mentions his brother Robert. I don't suppose it will, though. I suspect that I will never be able to
conclusively prove a descent from Robert Biscoe and Susan née Lane, although the choice of children's names is suggestive of something.
Thanks for all your help so far.
Martin