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FERNS IMAGES
1, 2. Filicalean ferns are common woodland plants, and range in size from understory "herbs" to larger trees.
3. The circinate vernation of most ferns results in the characteristic fiddlehead appearance of the young leaves seen here.
4. Transverse section of a fern rhizome, showing a slightly dissected stele with a single leaf gap. Note the distribution of phloem to either side of the xylem.
5. A more highly dissected dictyostele showing numerous leaf gaps.
6. A transverse section through a fern leaf (megaphyll), showing the spongy mesophyll and abaxial stomates.
7. A sorus, or cluster of leptosporangia, covered by an indusium. These occur on the reproductive leaves of the plant.
9. The prothallus type gametophyte of a typical fern. The meristem is located in the notch of this heart-shaped plant.
10. A single antheridia, as seen on the ventral side of the fern gametophyte.
11. A cluster of archegonia, located just below the apical notch. In most ferns archegonia are produced after antheridia; i.e., they are protandrous.
