I wonder do any of our participants trace their descent from Costains originating anywhere other than Rushen/Arbory?

I am very interested in families which appear to be quite numerous and well distributed around 1500, but later become concentrated in a particular part of the Island.

If you look at Talbot's transcriotion, in the surname index to tenants, there are

Mac Austesyn x 5
MacCorsten x 1
MacCosten x 1
MacCostein x 1

The three last were spread around the Isamd.

NGC