« Reply #31 on: Tuesday 25 September 07 10:05 BST (UK) »
I think the John Corless might be a red herring. I've found him in 1861 and 1851, and, although he has several children, the only daughters in those years are Sarah and Ann.
1861 RG9/2678 folio 26 pg 5
1851 HO107/2181 folio 211 pg 56

Cornwall: Allen, Bevan, Bosisto, Carnpezzack, Donithorn, Huddy, James, Retallack, Russell, Vincent, Yeoman
Cards: Thomas (Llanbadarn Fawr)
Glam: Bowler, Cram, Galloway, James, Thomas, Watkins
Lincs: Coupland, Cram
Mon: Cram, Gwyn, John, Philpot, Smart, Watkins
Pembs: Edwards (St. Dogmael's)
Yorks: Airey, Bowler, Elliott, Hare, Hewitt, Kellett, Kemp, Stephenson, Tebb