a class of cone-bearing gymnosperms dating from the Carboniferous; most are substantial trees; it includes the classes Pinopsida (subdivision Pinophytina) and Ginkgopsida (subdivision Ginkgophytina) and Taxopsida (subdivision Taxophytina) which in turn include the surviving orders Coniferales and Taxales (yews) and sometimes Ginkgoales as well as extinct orders such as Cordaitales (of the Carboniferous and Permian) and Volztiales (of the Permian-Jurassic).