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the part of the stem in a plant seedling between the cotyledons and the first true leaves (the first internode). In embryos the epicotyl is a conoid outgrowth consisting of primary formative tissue, or meristem. In plants with aboveground shoot formation the epicotyl and the cotyledons appear above the surface of the soil (for example, in beans and melons). In plants having underground shoot development the cotyledons remain in the soil, and the epicotyl is bent into a loop and then straightened; it carries the bud with the first leaves to the surface, toward the light (for example, in peas, plums, and oaks).