Cecil Calvert, second Lord Baltimore.
Cecil Calvert (1606-1675) was George Calvert's son and heir. In 1632, Cecil became the second Baron of Baltimore and the first Lord of Proprietary of both Avalon and Maryland.
From Justin Winsor, ed., Narrative and Critical History of America: English Explorations and Settlements in North America 1497-1689, Vol. III (Boston: Houghton, Mifflin & Company, 1884) 546.