As part of critical review of the Geometroidea and Noctuoidea described by Linnaeus the species described by Carl Clerck (1710-1765) are reviewed. Clerck (1759) described 25 nominal species of Geometroidea and Noctuoidea, all of Swedish origin, 22 of which are currently regarded as valid. 17 lectotypes are designated, 9 from the Clerck Collection, 6 from the Linnaeus Collection, and 2 from De Geer's collection. The name fulvago Clerck is a new junior synonym of Agrochola helvola (Linnaeus, 1758). The name "fulvago: Linnaeus 1761" is a later citation of Oerck's name, and thus should not replace the name Xanthia sulphurago (Denis & Schiffermüller, 1775). The name hepatica Clerck is a new senior synonym of Lithophane socia (Hufnagel, 1766). For Polia hepatica auct., nec Clerck, the name tincta Brahm, 1790 is available.