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Hilum at h; micropyle at d.

Caulicle at b; cotyledon at a; plumule at p.

Caulicle at c; roots emerging at m; plumule at p.

o, plumule: n to p, epicotyl.

Germination of Monocotyledons.—Thus far we have studied dicotyledonous seeds; we may now consider the monocotyledonous group. Soak kernels of corn. Note that the micropyle and hilum are at the smaller end (Fig. 24). Make a longitudinal section through the narrow diameter; Fig. 25 shows it. The single cotyledon is at a, the caulicle at b, the plumule at p. The cotyledon remains in the seed. The food is stored both in the cotyledon and as endosperm, chiefly the latter. The emerging shoot is the plumule, with a sheathing leaf (p, Fig. 26). The root is emitted from the tip of the caulicle, c. The caulicle is held in a sheath (formed mostly from the seed-coats), and some of the roots escape through the upper end of this sheath (m, Fig. 26). The epicotyl elongates, particularly if the seed is planted deep or if it is kept for a time confined. In Fig. 27 the epicotyl has elongated from n to p. The true plumule-leaf is at o, but other leaves grow from its sheath. In Fig. 28 the roots are seen emerging from the two ends of the caulicle