Saw this crest on ebay. The motto is 'Air muir's air tir' which I believe is the gaelic version of the latin 'Per mare per terras' which is generally accepted as one of the clan macdonald mottos'.
I know the new Keppoch chief uses the gaelic version but the centre piece arm brandishing a sword has me stumped for any possible MacDonald connection other than it is similar to Clanranald.
Anyone any suggestions?