1. Stems - I

2. Primary Structure of Stems Dermal – Epidermis Ground Tissue –Cortex –Pith –Other Vascular Tissue – vascular bundles –Collateral VB –Bicollateral VB –Concentric VB

4. Acorus stem with endodermis

5. Amphivasal VB

6. Morphological concepts used to explain primary anatomy Stelar Theory Leaf Trace Theory

7. Types of steles Protosteles --------------> Siphonosteles-------------->

8. Protosteles have a central core of vascular tissue surrounded by cortex (not shown) Xylem Phloem

9. Haplostele in Psilotum rhizome

10. Haplostele in Selaginella root

11. Actinostele in Psilotum stem

12. Actinostele in Ranunculus root

13. Plectosteles in Lycopodium stems

14. Siphonosteles have a central pith surrounded by a cylinder of vascular tissue Ectophloic Siphonostele Amphiphloic siphonostele Dictyostele

15. Ectophloic siphonstele in fern rhizome with a ring of xylem surrounded by a ring of phloem

16. Amphiphloic siphonostele in a fern rhizome with two rings of phloem on each side of xylem

17. Leaf traces and leaf gaps

18. Siphonostele with a leaf gap and leaf trace

19. Dictyosteles are considered amphiphloic siphonosteles with overlapping leaf gaps

20. Modified siphonosteles

21. Eustele Dicots and gymnospermsMonocots

22. Evolution of stelar types

23. Flattened protostele in Selaginella stem Flattened haplostele? OR Actinostele with two arms?

24. Actinostele with irregular shape Or a plectostele with connections between xylem areas?

25. Stele in stem Asteroxylon (fossil member of Division Lycophyta)

26. Leaf traces originate at the apical meristem

27. Leaf traces

28. Anatomy of nodes Unilacunar with 2 traces Unilacunar with 1 trace Trilacunar with 3 traces Multilacunar with many gaps and many traces