Columella (botany)
Encyclopedia
Columel′la an axis of sterile tissue which passes through the center of the spore-case of moss
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Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
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