2. Diversity of Seedless Vascular Plants  Division Lycophyta 21.3 Seedless Vascular Plants Introduction to Plants  Sporophyte generation of lycophytes is dominant.  Reproductive structures produce spores that are club-shaped or spike-shaped. Lycopodium—wolf’s claw Chapter 21

3. Introduction to Plants  Two genera—Lycopodium and Selanginella 21.3 Seedless Vascular Plants Chapter 21  Have roots, stems, and small, scaly, leaflike structures

4. Division Pterophyta Introduction to Plants  Plant division includes ferns and horsetails Staghorn fern Hawaiian fern Aquatic fern Dryopteris 21.3 Seedless Vascular Plants Chapter 21

5.  Sporophyte produces roots and a thick underground stem called a rhizome, a food-storage organ. Introduction to Plants  The frond is part of the sporophyte generation of ferns. 21.3 Seedless Vascular Plants Chapter 21

6. Introduction to Plants  Fern spores form in a structure called a sporangium.  Clusters of sporangia form a sorus.  Sori usually are located on the undersides of fronds. Bird’s nest fern 21.3 Seedless Vascular Plants Chapter 21