Information from Lloyd D. Ellis:

http://wc.rootsweb.ancestry.com/cgi-bin/igm.cgi?op=GET&db=dubart&id=I785

ID: I785

Name: Margaret vch JON

RFN: 785

Change Date: 12 DEC 2003

Sex: F

Birth: 1640 in Montgomeryshire

Change Date: 23 DEC 1998

Death: 1703 in Philadelphia County,, PA

Marriage 1 Alexander EDWARDS b: 1640 in Llanycil Parish ?

Married: 7 JUL 1664 in Llanycil Parish ?

Children

1. Margaret EDWARDS b: ABT 1684 in Llanycil Parish

According to the Welshpedia page on Welsh Surnames:

http://www.welshpedia.co.uk/wiki/wales/index.php?title=Welsh_Surnames

Fixed family names are a recent introduction to Wales. Before they were imposed for legal purposes, patronymic surnames were used.

The Welsh used an ancient patronymic naming system whereby the children of a marriage took their father's forename as their surname. As a result surnames were not fixed, and changed from generation to generation: so that Evan son of Thomas William would be known as Evan Thomas; Evan's son, John would be John Evan; John's son Rees would be Rees John; and David's son, James, would be James David.

Names such as Edward and William sometimes added an 's', becoming Edwards and Williams. Names ending in 's' like Thomas remained unchanged.

Traditionally women kept their maiden names when they married as there was no surname for them to adopt. The terms verch or ferch, meaning "daughter of", and abbreviated to vch or vz, were sometimes used, though they are rarely found in parish register entries.

This practice continued up until the early 1800s in some areas, with rural areas clinging to the patronymic system longer than urban ones. Areas where English influence was strong abandoned patronymics earlier, as did town families and the wealthy.

Welsh communities are full of families bearing the same few surnames but who are completely unrelated, and it cannot be claimed that everyone named Jones or Evans must be related to everyone else named Jones or Evans.

Patronymics were essentially a genealogical history of the family, where one generation was connected to another by ap, from map (mab in modern Welsh), meaning "son of".

Names such as Llewelyn ap Dafydd ab Ieuan ap Griffith ap Meredith were not uncommon. At the end of the 19th century, this practice ceased and ap was usually combined with one name to yield surnames such as Upjohn (from Apjohn) and Powell (from Aphowell).

Ben notes: Margaret is not a typical Welsh name, according to the list that followed - Marged would have been the Welsh equivalent. Other Welsh variants included Marared, Mared, Margaid, and the nickname Megan or Meghan.