1. Divisions of Seed Plants

2. Div: Gnetophyta The “Gnetophytes” n 1. Are gymnosperms. n 2. Have vessels as well as tracheids. n 3. Interval between pollination and fertilization is short. n 4. Mostly dioecious. n 5. Embryogengy has a more limited free nuclear period. n 6. Pollen chamber extends to female gametophyte - short pollen tube rapid fertilization.

3. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n 1. Resembles whisk ferns. n 2. Most of the photosynthesis occurs in new branches. n 3. Leaves appressed against stem. n 24-3

4. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n 1. Resembles whisk ferns. n 2. Most of the photosynthesis occurs in new branches. n 3. Leaves appressed against stem. n 24-3

5. Div: Gnetophyta Order: Ephedrales Genus: Ephedra

6. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n 1. Resembles whisk ferns. n 2. Most of the photosynthesis occurs in new branches. n 3. Leaves appressed against stem. n 4. Compound megastrobili and simple microstrobili. n 24-6 C, D, E

7. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n 1. Resembles whisk ferns. n 2. Most of the photosynthesis occurs in new branches. n 3. Leaves appressed against stem. n 4. Compound megastrobili and simple microstrobili. n 24-6 C, D, E

8. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n 1. Resembles whisk ferns. n 2. Most of the photosynthesis occurs in new branches. n 3. Leaves appressed against stem. n 4. Compound megastrobili and simple microstrobili. n 24-6 C, D, E

9. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n Young ovule:

10. Div: Gnetophyta Order: Gnetales Geneus: Ephedra n Mature ovule: n 24-12

11. Div: Gnetophyta Order: Welwitschiales Genus:Welwitschia n 1. Long underground stems. n 2. Straplike leaves - basal meristem. n (intercalary growth)