I played around with the picture and decided that the initial letter was a J since it looked very similar to the J of Joseph. There are not many names that long wwhich begin with a J and tall letters in the middle. It was also obvious that the upstroke of the J in Joseph might confuse the name above.
So searched for a Henry Turner born cir 1875 in Staffordshire. There are not that many - one of them had the father Jonathan and he lived in the right place! Put it down to luck.
To find Jonathan's parent's you would need to search backwards through the census. But whether he was born just before or just after civil registration began will possibly make it difficult.
Looking at 1851 first, two Jonathan Turners of about the right age: one born 1837 in Bilston, the other b 1841 in Sedgley. Since the Jonathan I found was born in Sedgely, it looks as if he cannot remember his proper age by 1891
To confirm which one it is, you need to find his marriage and get the certificate which will show his father's name. The Sedgley one was still unmarried in 1861, but married to Caroline in 1871. So this is your man. Caroline was Caroline Jones and they married in Dec qtr 1868 in Wolverhampton RD. His parents were Thomas and Sarah according to the census. His birth registration may be (I stress may be) in Dudley RD Sept 1840 Vol 18 p 291
Nell