Thanks Nell - so there were two!. I'm a north of the river person. I did wonder why the St George's Bloomsbury was in with Southwark!
I think my link refers to the amalgamation but says that it was re-named Southwark in 1901
re-quote
In 1869, the parishes of Southwark, St George the Martyr and Newington, St Mary were added to the St Saviour's Union which was then renamed the Southwark Union in 1901
gnu
PS - is there a link to St George the Martyr, Southwark in Genuki - I can only get the Bloomsbury one up