6. M.Herennius, was consul in B. C. 93. (Fast.; Obseq. 112.) Although a plebeian and an indifferent orator, he carried his election against the high-born and eloquent L. Marcius Philippus. (Cic. Brut. 45, pro Muren. 17.) Pliny (Plin. Nat. 19, 3) mentions the consulate of Herennius as remarkable for the quantity of Cyrenaic silphium--ferula Tingitana (Sprengel, Rei Herbar. p. 84.), then brought to Rome. This costly drug was worth a silver denarius the pound; and the mercantile connections of the Herennii in Africa may have caused this unusual supply.
A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890