1. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Evolved during the Devonian Period (395 mya); one of the dominants during the Caboniferous Period.(345-280 mya).

2. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n 1. Silica in cell walls. n 2. Leaves microphyllous; small and scalelike; form whorls at nodes. n 3. Vegetative and fertile shoots. n 4. Large sporophyte (2n) & n small gametophyte (n) - both n independent. n 5. Extensive rhizomes with roots n that branch irregularly. n 6. All branching (leaves & roots) n whorled at nodes. n 7. Growth from the base of each n segment (intercalary). n 8. Are homosporous.

3. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Intercalary meristem –adds length to the internodes

4. K: Plantae Div: Sphenophyta “horsetails or scouring rushes”

5. n *All of the silicified cells are in the epidermis. n *Stomates of epidermis sunken in E. hymanale. n *Carinal canals for water conduction. n *Central canal and vallecular canals n for gas exchange. n Endodermis –outside layer around stele n Pericycle –single cell layer just inside of endodermis –gives rise to branch roots

6. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous

7. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n sporangiophore and sporangia

8. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n tapetum and tapetal plasmodium

9. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n green spores germinate quickly.

10. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n spores with elators

11. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n green spores germinate quickly.

12. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n meiosis n spores (n) germinate ----------> gametophyte (n) n 2 types of gameophytes: male and monoecious n antheridia & archegonia

13. K: Plantae Div: Sphenophyta “horsetails or scouring rushes” n Reproduction: homosporous n fertilization --> zygote (2n) --> sporophyte (2n) n

14. K: Plantae Div: Psilophyta “Whisk Ferns” n Evolved during the late Devonian Period (approx. 375 mya)

15. K: Plantae Div: Psilophyta “Whisk Ferns” n 1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x- section. n 2. No roots but have rhizoids with micorrhiza.

16. K: Plantae Div: Psilophyta “Whisk Ferns” n 1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x- section. n 2. No true roots but have rhizoids with micorrhiza. n 3. Bears small leaf-like appendages, or prophylls. n (no vascular tissue but leaf traces) n 4. Spores (n) are produced in trilobed structures on the tips of short branches called synangia.

17. K: Plantae Div: Psilophyta “Whisk Ferns” n 4. Spores (n) are produced in trilobed structures on the tips of short branches called synangia. n tapetal plasmodium n sporangial wall

18. K: Plantae Div: Psilophyta “Whisk Ferns” n Psilophyte spores (n) are kidney-shaped. n

19. K: Plantae Div: Psilophyta “Whisk Ferns” n Psilophyte spores (n) are slow to develop into monoecious gametophytes (n). n archegonia

20. K: Plantae Div: Psilophyta “Whisk Ferns” n Psilophyte spores (n) are slow to develop into monoecious gametophytes (n). n n antheridium

21. K: Plantae Div: Psilophyta “Whisk Ferns” n Development from the fertilized egg (zygote 2n) proceeds in the archegonium. n

22. K: Plantae Div: Psilophyta “Whisk Ferns” n Eventually the young sporophyte (2n) becomes the mature plant body (2n). n

23. K: Plantae Div: Psilophyta “Whisk Ferns” n Stem and rhizome development: n immature stem tip - promeristem, protoderm, ground meristem, procambium

24. K: Plantae Div: Psilophyta “Whisk Ferns” n Mature stem - n

25. K: Plantae Div: Psilophyta “Whisk Ferns” Genus: Tmesipteris