I have just noticed this message. By coincidence I have a very great regard for Bishop Colenso and my house in named after him, "Colenso Cottage". His wife's maiden name is spelt Bunyon in all the references I have noted, but of course that was a quite common variation for a name spelt in many ways. Unfortunately, I have not been able to trace her father's family back very far. She came from Norfolk and she was also a very remarkable woman, among other things, author of "Letters from Natal".