Leonard, a physician who flourished in the reign of Charles II., was one of the most excellent and laborious botanists of that or any other age. He was author of the Phytophagia Philkenetiana, the Almagesticum Britannicum, and other works of a similar kind, on which he spent the greater part of his life and fortune. His Phytophagia is mentioned with the highest praise in the Philosophical Transactions for February 1696-1697. His Opera Botanica, with cuts, were printed at London, in six vols. folio, in 1720.