Re: Sewing up holes in hides?
If there are no pieces of hide missing. (You will be able to tell after fleshing) sew along the hole don't remove anything. I use curved medical needles and heavy brown thread that looks like carhart material. Color isn't important. Dental floss, as Gill said and a regular sewing needle will get the job done. Keep your stitches close.
If you have a small bald spot in a hide you want to remove that's when you want to cut the oval hole.
"Little minds are tamed & subdued by misfortune, but great minds rise above them"