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Lycophyta-Selaginellales-2

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The Leaves are Microphylls.

Vegetative Leaves are produced in four ranks.

In most cases the two ranks of Dorsal Leaves are small while the Ventral Leaves are relatively broad and are displayed laterally. This gives the plants a flat appearance & places all four ranks of leaves in one plane. This maximizes the light-exposure of  leaves on the dorsal side of the plant. This is a good adaptation for a plant that lives on the forest floor because there will be no leaf "autoshading".

This is a good example of Anisophyllus leaf production.

Sporophylls are assembled into Cones. The cones are usually square in cross-section. This makes it easy to distinguish between Selaginella & Lycopodium.

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Dorsal & Ventral Leaves
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Leaves & Cones

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A prostrate form: All of the leaves face upwards virtually avoiding
self-shading"

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Selaginella Cones

Selaginella is Heterosporous

Microsporangia occur on Microsporophylls

Megasporangia occur on Megasporophylls

The Sporangia differ in shape because the large Megaspores alter the outline of the Megasporangium.

However, there are no discernable differences between the two Sporophylls.

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