Embryos of monocotyledons possess only one cotyledon. In the grass family the cotyledon is called scutellum that is situated towards one side (lateral) of the embryonal axis.
At its lower end, the empryonal axis has the radical and root cap enclosed in an undifferentiated sheat called coleorrhiza . The portion of the embryonal axis above the level of attachment of scutellum is the epicotyl. Epicotyl has a shoot apex and a few leaf primordia enclosed in a hollow foilar structure , the coleoptile.
