No one knows where the expression "to grin like a Cheshire cat" originated, but it wasn't with Carroll. The Cheshire cat is a well-known character in Alice's Adventures in Wonderland, but the expression, meaning a sneering smile that shows the gums, existed long before he wrote the book. There is no such breed of cat.
I have no idea... and I lived in Cheshire. As a Kid, we all presumed it came from the book?... But now I find it existed before the book....
-x-clacks-GNU Terry Pratchett----Release the Clan Mac Feegle, awae hame ye scunners.[p]Most of my Job is avoiding Stupid. ...You cant Fix Stupid. Especially when you turn Left at Hammerhead.