James Hyndman MacDonnell FRSA (1885-13 September 1964) was a solicitor and Labour Party politician. The son of Mark Antony MacDonnell and Mary Frances nee Hyndman, he was born in Marylebone. His father was a doctor of medicine born in County Mayo, Ireland, while his mother was born in Boston, Massachusetts, USA. He became a solicitor, with a practice in Southampton Street, The Strand from 1915–41 and in Maiden Lane, Covent Garden from 1941 until his death. He died at his home at Cadogan Square, Chelsea, aged 79.