Sub-class I. Gymnospermae.—Gymnosperms.

Gymnogens, Lindl.

Characters.—Ovules naked, in an open carpellary leaf or pervious disk, fertilized by direct application of the pollen to the foramen (micropyle) without the intervention of stigma, style, and ovary. Ligneous tissue porous at the sides, the pores being apparently surrounded each by one or two circles.

This sub-class includes two orders: 1. Cycadeae, or Cycads; 2. Pinaceae, or Conifers.

The Elements of Materia Medica and Therapeutics, Vol. II, 3th American ed., was written by Jonathan Pereira in 1854.