Their leaves usually have many veins and their reproductive organs and internal structures are different from those of the Lycophytina plants. They have many slender, highly branched aerial stems by which the plants spread. They reproduce from spores. These are rare plants and can be found in tropical and subtropical regions. Stems are hollow except at the nodes, giving them a jointed appearance.
Most ferns have large leaves called fronds which are usually made up of smaller leaflets.
They reproduce by means of spores. Next to flowering plants, ferns are the most diverse group of plants in the division Tracheophyta. Gymnosperms reproduce by means of naked, or uncovered, seeds. Many gymnosperms are evergreens with a wide variety of leaf structures. Conifers, cycads, ginkgoes, and gnetaleans are in this class.