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Lepidlemmphyta

Lepidlemmphyta

Lepidlemmphyta are tree like plants trees possessing branching rooting organs, called stigmaria, anchoring the plant in shallow soil. The stigmaria are spirally arranged roots. Attached to the stigmaria is a tall, thick trunk which has few branches for most of its length. The trunk terminates in a crown of simple branches were covered with spirally arranged grass-like leaves.
The trunk produces very little, if any, wood. Instead, most structural support comes from a thick, scaley "bark". This scalebark consists of diamond-shaped scales, composed of green photosynthetic tissue, dotted with stomata through which carbon dioxide from the air diffuses into plants. It remains around the trunk in a rigid layer that does not flake off. As the tree grows, the scales expanded to accommodate the increasing width of the trunk.
At the end of the branches are oblong reproductive monosporangiate cones, containing highly specialized megasporangia which mimic certain seed habit. A single megaspore remains within the megasporangium, and the megasporangium remains tucked inside a leafy sporophyll that encloses it. The entire cone breaks up and these units thus serve as propagules. This dispersal unit acted as a small boat capable of aquatic dispersal.