Monica,
Here is a census return for 1911 which lists Margaret as head of house. Henry Lynch came originally from Arklow when the congested district board brough fishermen and their boats to Aran in order to help modernise the island's fishing industry. The Lynchs were associated with the sea and with lighthouse keeping. The last of the Lynchs to live on Aran was Mary (Ciss) who died some years ago at the age of 99. Tommy O'Rourke was involved in the making of Robert Flaherty's Man of Aran in 1932. Another very skilled seafarer who was part of the shark hunting crew.That surname has also now died out on Aran
http://www.census.nationalarchives.ie/reels/nai002386030/ Mike.