Surely on the E & W birth certificates, pre 1969 if there are names in the space under the column heading "Name, if any" they are legally the given names, even if they may well be surnames within the family.
May I also suggest that the baby does not actually have a surname, and even if the name of the father is provided and even if the father is the informant, that is not where we should anticipate finding baby's surname.
Surely pre 1969, E & W births have the baby's surname coming directly from the column "Name and Maiden Surname of the Mother". So in the example that Sloe Gin has provided, baby George gains his surname from the name his mother was recorded as .... Mary Ann READ. Yes, George's dad was James READ but that's not why George would likely be George READ.
I can assure you that in New South Wales, Australia until 1969, baby's birth registrations had no provision for a separate column giving a surname for baby. I can further assure you that among my retired ancient living rellies are former senior officers of NSW BDM. They assure me that no one ever believes them BUT they know a child's surname comes from the surname that MUM was known by. If a married women in that era, she was likely known by the surname of her husband. NSW inherited that habit from .... England & Wales, and not from Scotland.
JM
and
Perhaps you are looking at a "short form" rather than the "long form" document.
JM.
NSW bdm abandoned the use of "extracts" once it had centralised birth registrations to its Head Office, Sydney and was fully EDP puterised! But my trusty rellies, retired Senior Officers from NSW BDM, assure me that when Extracts were the 'easy option' and were typed up at the local deputy registrar's offices through NSW, that the clerks doing the typing were required to use the surname from the local register's originals, and they were required to refer to the column for the Mother's name, recorded in that specific column. NO, NOT mum's former name, but the name she was recorded as on the registration. YES, if a married woman, then pre 1969, following from E & W traditions, mum's surname would match her husband's surname. It is important to also recognise that the statute laws of NSW governed (and still govern) NSW BDM, but that back in the 1850s when they were initially being drawn up, the experienced legal bods (drafters) were mainly educated in England, often were born in England, and the practices, rules and regulations were similar in purpose to English ones. This tradition continued for decades, perhaps even into the 1970s when the Commonwealth of Australia's White Australia Policy was finally abandoned.
So, my retired rellies are quite sure that for example, when a child started school, and someone needed to attend to enrolment and a surname was needed, the child's surname comes from their Mum. Back in the era of shame due to concerns about illegitimacy, the
baby's school child's surname came from the surname that the Mum was known by at that time.
My ancient living relatives thank AntonyMMM and simply note that "the down under lot must have mis-understood the accents of the English when following their lead".
JM EDIT to strike through babys and replace it with school child's