Hello Angela If you can give me details of your Cowans I will look through my records. The Cowans seemed to drop the Mc in the 19th century as they thought it might be easier to get work in the south without it - or possible some had it dropped for them.
Ther McCowans are supposed to originate from the MacDougalls of Reray (various spellings) at Kilninver, south of Oban.