Is Mary and Martha the same person?

[flower fairy]

Thank you to everyone who has answered. I may pop along to the record office to double check my original notes. It is a stones throw from me and i haven't actually been to the new one yet. I am thinking that the mum is Martha and somewhere it has been transcribed down wrong, possibly by me 

[LizzieL]

I am thinking that the mum is Martha and somewhere it has been transcribed down wrong, possibly by me

I found it on Ancestry as mother Mary but that was transcribed, so maybe mistake on original record.
I did come across one register where a lot of spaces were left for mother's name on a baptism record. Some had been filled in later - different pen, darker ink, short names written large to fill space, long names squeezed so it was obvious a later addition. I don't know whether this meant that the father had brought baby to be baptised when a few days old and mum wasn't there because she was still recovering from the birth. I think it was probably a Dorset register, most of my rellies pre 1837 were from there.